Low volatility herbicidal compositions

ABSTRACT

The present invention relates generally low volatility herbicidal compositions comprising at least one auxin herbicide and at least one monocarboxylic acid, or monocarboxylate thereof. The invention further relates generally to methods for preparing and using such low volatility herbicidal compositions, including methods for controlling auxin-susceptible plant growth on agricultural and non-agricultural lands.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. Provisional Application Ser. No. 61/722,700 filed on Nov. 5, 2012, and U.S. Provisional Application Ser. No. 61/794,769 filed on Mar. 15, 2013. The entire text of those provisional applications is incorporated by reference into this application.

FIELD OF THE INVENTION

The present invention relates generally to low volatility herbicidal compositions comprising at least one auxin herbicide and at least one monocarboxylic acid, or monocarboxylate thereof. The invention further relates generally to methods for preparing and using such low volatility herbicidal compositions, including methods for controlling auxin-susceptible plant growth on agricultural and non-agricultural lands.

BACKGROUND OF THE INVENTION

Auxin herbicides, such as dicamba (3,6-dichloro-2-methoxybenzoic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid), are commonly used to control auxin-susceptible plant growth on both agricultural and non-agricultural lands. Volatility and drift, however, are problems frequently associated with these herbicides. Volatile auxin herbicides can, under certain application conditions, vaporize into the surrounding atmosphere and migrate from the application site to adjacent crop plants, such as soybeans and cotton, where contact damage to sensitive plants can occur. Spray drift can be attributed to both volatility and the physical movement of small particles from the target site to adjacent crop plants.

Prior approaches to reducing herbicide volatility have included efforts to identify herbicide salts and formulations exhibiting lower volatility. As one example, the diglycolamine salt of dicamba exhibits a lower volatility than the dimethylamine salt of dicamba. Although lower volatility auxin herbicide salts and formulations have been reported, further reduction in the volatility and off-target movement of auxin herbicides is still desirable.

Another approach to reducing auxin herbicide volatility has focused on encapsulation, for example, absorbing the auxin herbicide into solid phase natural or synthetic polymer, or microencapsulating the auxin herbicide in a polymer shell. Due to technological challenges and other factors, however, commercial encapsulation products that satisfactorily reduce auxin herbicide volatility have not been developed.

Accordingly, auxin herbicide compositions having reduced volatility relative to currently available compositions would be desirable, particularly reduced-volatility compositions that exhibit no significant reduction in herbicidal effectiveness relative to currently available compositions.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, the present invention provides herbicidal compositions comprising at least one auxin herbicide; at least one monocarboxylic acid, or agriculturally acceptable monocarboxylate thereof; and, optionally, a non-auxin herbicide; wherein the compositions exhibit reduced volatility relative to an otherwise identical composition lacking the monocarboxylic acid or monocarboxylate thereof. In one embodiment, the auxin herbicide is selected from dicamba, or a agriculturally acceptable salt or ester thereof, and 2,4-D, or an agriculturally acceptable salt of ester thereof. In one embodiment, the composition comprises an acetate salt. In another embodiment, the non-auxin herbicide is glyphosate, or an agriculturally acceptable salt thereof.

In another aspect, the invention provides a herbicidal adjuvant composition comprising a monocarboxylic acid, or monocarboxylate thereof, and, optionally, an alkali metal phosphate, that can serve as the source of monocarboxylic acid, or a monocarboxylate thereof, used in the preparation of the herbicidal compositions of the present invention.

In another aspect, the invention provides methods of reducing the volatility of an auxin herbicide, wherein the methods comprise the step of contacting an auxin herbicide with a volatility-lowering effective amount of a monocarboxylic acid, or a monocarboxylate thereof, thereby reducing the volatility of the auxin herbicide.

In another aspect, the invention provides methods of controlling the growth of auxin-susceptible plants, wherein the methods comprise applying to the auxin-susceptible plants a herbicidal composition application mixture comprising at least one auxin herbicide; at least one monocarboxylic acid, or monocarboxylate thereof; and, optionally, a non-auxin herbicide; wherein the application mixture exhibits reduced auxin herbicide volatility relative to an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.

In another aspect, the invention provides methods of controlling off-site movement of an auxin herbicide, wherein the methods comprise contacting the auxin herbicide with a volatility-lowering effective amount of a monocarboxylic acid, or a monocarboxylate thereof, prior to application of the auxin herbicide.

In another aspect, the invention provides methods of counseling an individual regarding the preparation and/or application of an auxin herbicide.

Further benefits of the present invention will be apparent to one skilled in the art from reading this patent application. The embodiments of the invention described in the following paragraphs are intended to illustrate the invention and should not be deemed to narrow the scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides herbicidal compositions comprising an auxin herbicide wherein the compositions exhibit reduced volatility and/or vapor drift upon application with respect to the auxin herbicide. Specifically, the compositions comprise, in addition to the auxin herbicide, at least one monocarboxylic acid, or monocarboxylate thereof, in an amount sufficient to reduce the volatility of the auxin herbicide relative to an otherwise identical composition lacking the monocarboxylic acid, or monocarboxylate thereof.

It has been discovered that the addition of a sufficient amount of a monocarboxylic acid, or a monocarboxylate thereof (particularly a non-ammoniated monocarboxylate salt), to a herbicidal composition concentrate or a herbicidal composition application mixture (e.g., a “tank mix”) results in a significant reduction in the level of volatile auxin herbicide detected. For some compositions, the amount of volatile auxin herbicide present is actually below the detection level of sophisticated analytical methods such as liquid chromatography-mass spectrometry (LC/MS). As compared to auxin compositions known in the art, it is believed that the compositions of the present invention provide enhanced protection from off-target crop injury while maintaining comparable herbicidal efficacy on auxin-susceptible plants located in the target area.

The present invention is additionally directed to methods for controlling the growth of auxin-susceptible plants, comprising applying the herbicidal compositions of the present invention to such plants in accordance with the guidance provided below.

A. AUXIN HERBICIDE COMPONENT

The term “auxin herbicide” refers to a herbicide that functions as a mimic of an auxin plant growth hormone, thereby affecting plant growth regulation. Examples of auxin herbicides that are suitable for use in the herbicidal compositions of the present invention include, without limitation, benzoic acid herbicides, phenoxy herbicides, pyridine carboxylic acid herbicides, pyridine oxy herbicides, pyrimidine carboxy herbicides, quinoline carboxylic acid herbicides, and benzothiazole herbicides.

Specific examples of auxin herbicides include:

-   Dicamba (3,6-dichloro-2-methoxy benzoic acid); -   2,4-D (2,4-dichlorophenoxyacetic acid); -   2,4-DB (4-(2,4-dichlorophenoxy)butanoic acid); -   Dichloroprop (2-(2,4-dichlorophenoxy)propanoic acid); -   MCPA ((4-chloro-2-methylphenoxy)acetic acid); -   MCPB (4-(4-chloro-2-methylphenoxy)butanoic acid); -   Aminopyralid (4-amino-3,6-dichloro-2-pyridinecarboxylic acid); -   Clopyralid (3,6-dichloro-2-pyridinecarboxylic acid); -   Fluoroxypyr ([(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxy]acetic     acid); -   Triclopyr ([(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid); -   Diclopyr; -   Mecoprop (2-(4-chloro-2-methylphenoxy)propanoic acid); -   Mecoprop-P; -   Picloram (4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid); -   Quinclorac (3,7-dichloro-8-quinolinecarboxylic acid); and -   Aminocyclopyrachlor     (6-amino-5-chloro-2-cyclopropyl-4-pyrimidinecarboxylic acid); -   including salts and esters thereof; racemic mixtures and resolved     isomers thereof; and combinations thereof.

In one embodiment, the herbicidal composition comprises dicamba, or an agriculturally acceptable salt or ester thereof. Examples of suitable dicamba salts include the N,N-bisdaminopropylimethylamine, monoethanolamine, dimethylamine (e.g., BANVEL®, ORACLE®, etc.), isopropylamine, diglycolamine (e.g., CLARITY®, VANQUISH®, etc.), potassium, and sodium salts, and combinations thereof. Commercially available sources of dicamba, and its agriculturally acceptable salts, include those products sold under the trade names BANVEL®, CLARITY®, DIABLO®, DISTINCT, ORACLE®, VANQUISH®, and VISION®.

In another embodiment, the herbicidal composition comprises an agriculturally acceptable dicamba salt, wherein the salt is selected from the group consisting of N,N-bis-[aminopropyl]methylamine, monoethanolamine, dimethylamine, isopropylamine, diglycolamine, potassium, and sodium salts, and combinations thereof.

Throughout the remainder of the description of the invention, where reference is made to dicamba, or an agriculturally acceptable salt or ester thereof, one skilled in the art will understand that the principles of the present invention apply to auxin herbicides generally, including those described above, and that the present invention is not limited to herbicidal compositions containing dicamba, or an agriculturally acceptable salt or ester thereof.

In another embodiment, the herbicidal composition comprises 2,4-D, or an agriculturally acceptable salt or ester thereof. Examples of suitable 2,4-D salts include the choline, dimethylamine, and isopropylamine salts, and combinations thereof. Examples of suitable 2,4-D esters include the methyl, ethyl, propyl, butyl (2,4-DB), and isooctyl esters, and combinations thereof. Commercially available sources of 2,4-D, and its agriculturally acceptable salts and esters, include those products sold under the trade names BARRAGE®, FORMULA 40®, OPT-AMINE®, and WEEDAR 64®.

In another embodiment, the herbicidal composition comprises an agriculturally acceptable 2,4-D salt, wherein the salt is selected from the group consisting of choline, dimethylamine, and isopropylamine salts, and combinations thereof.

In another embodiment, the herbicidal composition comprises an agriculturally acceptable 2,4-D ester, wherein the ester is selected from the group consisting of butyl (i.e., 2,4-DB) and isooctyl esters, and combinations thereof.

In another embodiment, the herbicidal composition comprises at least two auxin herbicides, for example, dicamba, or an agriculturally acceptable salt or ester thereof, and 2,4-D, or an agriculturally acceptable salt or ester thereof.

B. MONOCARBOXYLIC ACID/MONOCARBOXYLATE COMPONENT

“Monocarboxylic acid” refers to a hydrocarbon or substituted hydrocarbon containing only one carboxy functional group (i.e., R¹—C(O)OH). “Monocarboxylate” refers to a salt (i.e., R¹—C(O)OM wherein M is an agriculturally acceptable cation) or ester (i.e., R¹—C(O)OR² wherein R² is hydrocarbon or substituted hydrocarbon) of a monocarboxylic acid. In one embodiment, the composition comprises at least one monocarboxylate salt, which in aqueous compositions may be present, in whole or in part, in dissociated form as a monocarboxylate anion and the corresponding cation.

Representative monocarboxylic acids and monocarboxylates generally comprise a hydrocarbon or unsubstituted hydrocarbon selected from, for example, unsubstituted or substituted, straight or branched chain alkyl (e.g., C₁-C₂₀ alkyl such as methyl, ethyl, n-propyl, isopropyl, etc.); unsubstituted or substituted, straight or branched chain alkenyl (e.g., C₂-C₂₀ alkyl such as ethenyl, n-propenyl, isopropenyl, etc.); unsubstituted or substituted aryl (e.g., phenyl, hydroxyphenyl, etc.); or unsubstituted or substituted arylalkyl (e.g., benzyl).

In one embodiment, the herbicidal composition comprises a monocarboxylate salt having the formula R¹—C(O)OM, wherein R¹ is unsubstituted or substituted C₁-C₁₀ alkyl and M is a non-ammoniated, agriculturally acceptable cation. In another embodiment, the herbicidal composition comprises a monocarboxylate salt having the formula R¹—C(O)OM, wherein R¹ is unsubstituted C₁-C₆ alkyl and M is an alkali metal salt. In another embodiment, the herbicidal composition comprises a monocarboxylate salt having the formula R¹—C(O)OM, wherein R¹ is unsubstituted C₁-C₃ alkyl and M is an alkali metal salt selected from sodium and potassium. In another embodiment, the monocarboxylate salt is potassium acetate. In another embodiment, the monocarboxylate salt is sodium acetate.

The term “agriculturally acceptable salt” refers to a salt comprising a cation that is known and accepted in the art for the formation of salts for agricultural or horticultural use. In one embodiment, the salt is a water-soluble salt.

C. ALKALI METAL PHOSPHATE/ALKALI METAL CARBONATE

The herbicidal compositions of the present invention optionally may further comprise an alkali metal phosphate such as dipotassium phosphate. Dipotassium phosphate, for example, can provide additional buffering and/or water-conditioning for aqueous herbicidal compositions of the present invention. Dipotassium phosphate is particularly effective as a replacement for ammonium sulfate in herbicidal composition application mixtures prepared using hard water.

Similarly, the herbicidal compositions of the present invention optionally may further comprise an alkali metal carbonate, such as potassium carbonate, to provide additional buffering and/or water-conditioning for aqueous herbicidal compositions of the present invention.

In some embodiments, the herbicidal compositions of the present invention comprise an alkali metal phosphate. In other embodiments, the herbicidal compositions comprise an alkali metal carbonate. In still other embodiments, the herbicidal compositions comprise an alkali metal phosphate and an alkali metal carbonate.

D. NON-HERBICIDE ADDITIVES

The herbicidal compositions of the present invention optionally may further comprise conventional additives such as surfactants, drift reduction agents, safeners, solubility enhancing agents, thickening agents, flow enhancers, foam-moderating agents, freeze protectants, UV protectants, preservatives, antimicrobials, and/or other additives that are necessary or desirable to improve the performance, crop safety, or handling of the composition.

In one embodiment, the herbicidal composition comprises less than about 10 ppm of ammonium sulfate. In another embodiment, the herbicidal composition does not comprise ammonium sulfate.

In one embodiment, the herbicidal composition does not comprise an acid that is a non-monocarboxylic acid.

E. NON-AUXIN HERBICIDE COMPONENTS

The herbicidal compositions of the present invention optionally may further comprise at least one non-auxin herbicide. The term “non-auxin herbicide” refers to a herbicide having a primary mode of action other than as an auxin herbicide. Representative examples of non-auxin herbicides include acetyl CoA carboxylase (ACCase) inhibitors, acetolactate synthase (ALS) inhibitors, acetohydroxy acid synthase (AHAS) inhibitors, photosystem II inhibitors, photosystem I inhibitors, protoporphyrinogen oxidase (PPO or Protox) inhibitors, carotenoid biosynthesis inhibitors, enolpyruvyl shikimate-3-phosphate (EPSP) synthase inhibitor, glutamine synthetase inhibitor, dihydropteroate synthetase inhibitor, mitosis inhibitors, and nucleic acid inhibitors; salts and esters thereof; racemic mixtures and resolved isomers thereof; and combinations thereof.

Representative examples of ACCase inhibitors include clethodim, clodinafop, fenoxaprop-P, fluazifop-P, quizalofop-P, and sethoxydim.

Representative examples of ALS or AHAS inhibitors include flumetsulam, imazamethabenz-m, imazamox, imazapic, imazapyr, imazaquin, imazethapyr, metsulfuron, prosulfuron, and sulfosulfuron.

Representative examples of photosystem I inhibitors include diquat and paraquat.

Representative examples of photosystem II inhibitors include atrazine, cyanazine, diuron, and metibuzin.

Representative examples of PPO inhibitors include acifluorofen, butafenacil, carfentrazone-ethyl, flufenpyr-ethyl, fluthiacet, flumiclorac, flumioxazin, fomesafen, lactofen, oxadiazon, oxyfluorofen, and sulfentrazone.

Representative examples of carotenoid biosynthesis inhibitors include aclonifen, amitrole, diflufenican, mesotrione, and sulcotrione.

A representative example of an EPSP inhibitor is N-phosphonomethyl glycine (glyphosate).

A representative example of a glutamine synthetase inhibitor is glufosinate.

A representative example of a dihydropteroate synthetase inhibitor is asulam.

Representative examples of mitosis inhibitors include acetochlor, alachlor, dithiopyr, S-metolachlor, and thiazopyr.

Representative examples of nucleic acid inhibitors include difenzoquat, fosamine, metham, and pelargonic acid.

In one embodiment, the herbicidal compositions of the present invention further comprise a non-auxin herbicide selected from the group consisting of acetochlor, glyphosate, glufosinate, flumioxazin, fomesafen, and agriculturally acceptable salts thereof.

In one embodiment, the herbicidal compositions of the present invention further comprise glyphosate, or an agriculturally acceptable salt thereof. Suitable glyphosate salts include, for example, the ammonium, diammonium, dimethylammonium, monoethanolamine, isopropylamine, and potassium salts, and combinations thereof. In one embodiment, the glyphosate salts are selected from the group consisting of monoethanolamine, isopropylamine, and potassium salts, and combinations thereof.

In one embodiment, the herbicidal compositions of the present invention comprise dicamba, or an agriculturally acceptable salt or ester thereof, and glyphosate, or an agriculturally acceptable salt thereof. In another embodiment, the herbicidal compositions of the present invention comprise dicamba, or an agriculturally acceptable salt thereof; glyphosate, or an agriculturally acceptable salt thereof; and a non-ammoniated, agriculturally acceptable acetate salt. Commercially available sources of glyphosate, and its agriculturally acceptable salts, include those products sold under the trade names DURANGO® DMA®, HONCHO PLUS®, ROUNDUP POWERMAX®, ROUNDUP WEATHERMAX®, TRAXION®, and TOUCHDOWN®.

In one embodiment, the herbicidal compositions of the present invention comprise 2,4-D, or an agriculturally acceptable salt or ester thereof, and glyphosate, or an agriculturally acceptable salt thereof. In another embodiment, the herbicidal compositions of the present invention comprise 2,4-D, or an agriculturally acceptable salt or ester thereof; glyphosate, or an agriculturally acceptable salt thereof; and a non-ammoniated, agriculturally acceptable acetate salt.

F. COMPONENT LOADING

Suitable amounts, concentrations, and/or molar ratios of the auxin herbicide, monocarboxylic acid, or monocarboxylate thereof, and optional non-auxin herbicide and non-herbicide additive components of the herbicidal compositions of the present invention will depend to some extent upon whether the composition is a ready-to-use composition, a concentrate to be diluted with water prior to application (e.g., a “premix”), or a herbicidal composition prepared by combining two or more herbicide components, water, and, optionally, other non-herbicide components (e.g., a “tank mix”).

1. Herbicide Loading:

Concentrated herbicidal compositions of the present invention typically comprise on an acid equivalent basis (a.e.), for example, from about 120 to about 600 g a.e./L, from about 300 to about 600 g a.e./L, from about 350 to about 600 g a.e./L, from about 400 to about 600 g a.e./L, from about 450 to about 600 g a.e./L, or from about 500 to about 600 g a.e./L total herbicide loading. Additional examples of representative total herbicide loading include 120, 150, 200, 250, 300, 350, 400, 450, 500, 550, and 600 g a.e./L, and ranges thereof (i.e., from about 120 to about 150 g a.e./L, from about 150 to about 200 g a.e./L, from about 200 to about 250 g a.e./L, from about 250 to about 300 g a.e./L, from about 300 to about 350 g a.e./L, from about 350 to about 400 g a.e./L from about 400 to about 450 g a.e./L, from about 450 to about 500 g a.e./L, from about 500 to about 550 g a.e./L, from about 550 to about 600 g a.e./L total herbicide loading).

Ready-to-use herbicidal compositions and other herbicidal compositions of the present invention requiring no further processing prior to application (e.g., diluted concentrates, tank mixes, etc.) typically will comprise on an acid equivalent basis (a.e.) from about 0.1 g a.e./L to about 50 g a.e./L total herbicide loading.

In herbicidal compositions of the present invention comprising an auxin herbicide and a non-auxin herbicide, the weight ratio on an acid equivalent basis of the auxin herbicide to the non-auxin herbicide is typically no greater than about 50:1, for example, about 50:1, 25:1, 10:1, 5:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:5, about 1:10, or ranges thereof such as from about 50:1 to about 1:10, from about 50:1 to about 1:5, from about 50:1 to about 1:1, from about 50:1 to about 3:1, from about 50:1 to about 5:1, from about 50:1 to about 10:1, from about 25:1 to about 1:1, or from about 25:1 to about 3:1.

For any given auxin herbicide, one skilled in the art can readily determine using routine experimentation a minimum concentration of auxin herbicide and a minimum ratio of auxin herbicide to any additional auxin herbicides and/or non-auxin herbicides contained in the herbicidal composition that is desirable for the intended application.

2. Monocarboxylic Acid/Monocarboxylate Loading:

As previously noted, it has been discovered that the concentration of volatilized auxin herbicide in the vapor phase surrounding a herbicidal composition comprising an auxin herbicide and a monocarboxylic acid, or monocarboxylate thereof, is less than the concentration of volatilized auxin herbicide in the vapor phase surrounding a reference composition lacking the monocarboxylic acid or monocarboxylate, but otherwise having the same composition. In various embodiments, the concentration of volatilized auxin herbicide in the vapor phase surrounding a herbicidal composition comprising an auxin herbicide and a monocarboxylic acid, or monocarboxylate thereof, is less than 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, or 5% of the concentration of volatilized auxin herbicide in the vapor phase surrounding the reference composition lacking the monocarboxylate.

The herbicidal compositions of the present invention may comprise a single monocarboxylic acid, or monocarboxylate thereof, or a mixture of two or more monocarboxylic acids, or monocarboxylates thereof.

The monocarboxylic acid or monocarboxylate loading of the herbicidal composition generally will depend upon the auxin herbicide loading of the herbicidal composition, the salt form of the auxin herbicide, and the properties of any other components of the herbicidal composition, and will be an amount sufficient to reduce the volatility of the auxin herbicide relative to a reference composition lacking the monocarboxylic acid or monocarboxylate, but otherwise having the same composition. For example, the monoethanolamine and diethanolamine salts of dicamba are less volatile than the dimethylamine and isopropylamine salts of dicamba and the loading required for the less volatile salts may be less than the loading required for the more volatile salts. In addition, the loading of the monocarboxylic acid, or monocarboxylate thereof, can vary with the specific combination of auxin herbicide, optional non-auxin herbicide, and monocarboxylic acid, or monocarboxylate thereof.

In the herbicidal compositions of the present invention the molar ratio of the auxin herbicide to the monocarboxylic acid, or monocarboxylate thereof, is typically no less than about 1:10 and no greater than about 10:1. Representative molar ratios of auxin herbicide acid equivalent (a.e.) to total monocarboxylic acid, or monocarboxylate thereof, are, for example, from 1:10 to about 10:1, from about 1:5 to about 5:1, and from about 3:1 to about 1:3. In one embodiment, the molar ratio of auxin herbicide to monocarboxylic acid, or monocarboxylate thereof, is about 1:1.

3. Alkali Metal Phosphate/Alkali Metal Carbonate Loading

When the herbicidal composition comprises an alkali metal phosphate, such as dipotassium phosphate, the molar ratio of the alkali metal phosphate to the monocarboxylic acid, or monocarboxylate thereof, can range, for example, from about 1:5 to about 5:1, from about 3:1 to about 1:3, or from about 2:1 to about 1:2. In one embodiment, the molar ratio of alkali metal phosphate to monocarboxylic acid, or monocarboxylate thereof, is about 1:1.

When the herbicidal composition comprises an alkali metal carbonate, such as potassium carbonate, the molar ratio of the alkali metal carbonate to the monocarboxylic acid, or monocarboxylate thereof, can range, for example, from about 1:5 to about 5:1, from about 3:1 to about 1:3, or from about 2:1 to about 1:2. In one embodiment, the molar ratio of alkali metal carbonate to monocarboxylic acid, or monocarboxylate thereof, is about 1:1.

G. HERBICIDAL COMPOSITION EMBODIMENTS

The herbicidal compositions can be presented in various forms depending upon the intended use and handling properties desired. For example, the herbicidal compositions of the present invention can be prepared in dry powder form or in liquid form, particularly aqueous solutions or dispersions. The term “aqueous” as used in this application, however, is not intended to exclude the presence of non-aqueous (i.e., organic) solvents as long as water is present. Water is the predominant component of the ready-to-use compositions and tank mix compositions disclosed in this application.

Among the various composition presentations of the invention are the following:

(a) a ready-to-use aqueous herbicidal composition that can be applied to unwanted plants without the need for further dilution with water or other preparation;

(b) a herbicidal composition concentrate that is diluted with water, and optionally combined with other herbicide and non-herbicide materials, prior to application (including, e.g., dry mixes and premixes);

(c) a herbicidal composition application mixture prepared by diluting a herbicidal composition concentrate with water to form the herbicidal composition application mixture which then can be applied to auxin-susceptible plants;

(d) a herbicidal composition application mixture prepared by combining two or more separate components with water (e.g., a tank mix) to form the herbicidal composition application mixture which then can be applied to auxin-susceptible plants; and

(e) a herbicidal composition application mixture prepared by introducing separate feed streams to a spraying or application system so that the feed streams are co-mixed to form the herbicidal composition application mixture immediately prior to use.

In various embodiments, the herbicidal compositions (ready-to-use, liquid concentrate, tank mix, etc.) have a pH that is equal to or higher than the acid dissociation constant (pKa) of the monocarboxylic acid present in the composition. For example, in certain embodiments, the herbicidal compositions comprise acetic acid (which has a pKa of about 4.8) and have a pH equal to or greater than about 4.8. In the case of herbicidal compositions comprising dicamba and an effective amount of acetic acid, dicamba volatility generally decreases as composition pH increases with dicamba volatility reaching substantially non-detectable levels at a composition pH of about 5.2 as measured in a plant response study.

1. Illustrative Composition Embodiments Concentrates

One embodiment of the invention is directed to a herbicidal composition concentrate comprising:

at least one auxin herbicide; and

at least one monocarboxylic acid, or a monocarboxylate thereof;

wherein the concentrate satisfies one or more of the following conditions:

the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1;

the concentrate contains an amount of the monocarboxylic acid, or

monocarboxylate thereof, from about 0.25% to about 25% by weight of the concentrate;

the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and

the concentrate comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the concentrate by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical concentrate lacking the monocarboxylic acid, or monocarboxylate thereof.

In further embodiments, the herbicidal composition concentrate comprises at least one auxin herbicide selected from the group consisting of dicamba, or an agriculturally acceptable salt or ester thereof, and 2,4-D, or an agriculturally acceptable salt or ester thereof.

In further embodiments, the herbicidal composition concentrate comprises dicamba, or an agriculturally acceptable salt or ester thereof. In another embodiment, the concentrate comprises a dicamba salt selected from the group consisting of N,N-bis-[aminopropyl]methylamine, monoethanolamine, dimethylamine, isopropylamine, diglycolamine, potassium, and sodium salts, and combinations thereof.

In further embodiments, the herbicidal composition concentrate comprises 2,4-D, or an agriculturally acceptable salt or ester thereof. In another embodiment, the concentrate comprises a 2,4-D salt selected from the group consisting of choline, dimethylamine, and isopropylamine salts, and combinations thereof. In another embodiment, the concentrate comprises a 2,4-D ester selected from the group consisting of butyl (i.e., 2,4-DB) and isooctyl esters, and combinations thereof.

In further embodiments, the herbicidal composition concentrate comprises a monocarboxylate salt.

In further embodiments, the herbicidal composition concentrate comprises a C₁-C₆-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₅-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₄-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₃-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises acetic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises formic acid, or an agriculturally acceptable salt thereof.

In further embodiments, the monocarboxylate salt or acetate salt is a non-ammoniated salt. In another embodiment, the monocarboxylate salt or acetate salt is an alkali metal salt. In another embodiment, the monocarboxylate salt or acetate salt is a potassium salt. In another embodiment, the monocarboxylate salt or acetate salt is a sodium salt.

In further embodiments, the herbicidal composition concentrate further comprises a buffer.

In further embodiments, the herbicidal composition concentrate further comprises an alkali metal phosphate, such as dipotassium phosphate.

In further embodiments, the herbicidal composition concentrate is a dry powder herbicidal composition.

In further embodiments, the herbicidal composition concentrate is an aqueous herbicidal composition.

In further embodiments, the herbicidal composition concentrate further comprises a non-auxin herbicide. In another embodiment, the non-auxin herbicide is selected from the group consisting of acetochlor, glyphosate, glufosinate, flumioxazin, fomesafen, and agriculturally acceptable salts thereof. In another embodiment, the non-auxin herbicide is glyphosate, or an agriculturally acceptable salt thereof. In another embodiment, the concentrate comprises a glyphosate salt selected from the group consisting of ammonium, diammonium, dimethylammonium, monoethanolamine, isopropylamine, and potassium salts, and combinations thereof. In another embodiment, the concentrate comprising a non-auxin herbicide satisfies one or more of the following conditions:

the sum of the concentration of Auxin herbicide and the concentration of non-auxin herbicide is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L;

the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.

2. Illustrative Composition Embodiments Application Mixtures

One embodiment of the invention is directed to a herbicidal composition comprising:

at least one auxin herbicide; and

at least one monocarboxylic acid, or a monocarboxylate thereof;

wherein the composition satisfies one or more of the following conditions:

the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1;

the composition contains an amount of the monocarboxylic acid, or monocarboxylate thereof, from about 0.1% to about 25% by weight of the composition;

the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and

the composition comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the composition by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical composition lacking the monocarboxylic acid, or monocarboxylate thereof.

In further embodiments, the composition comprises at least one auxin herbicide selected from the group consisting of dicamba, or an agriculturally acceptable salt or ester thereof, and 2,4-D, or an agriculturally acceptable salt or ester thereof.

In further embodiments, the composition comprises dicamba, or an agriculturally acceptable salt or ester thereof. In another embodiment, the composition comprises a dicamba salt selected from the group consisting of N,N-bis-[aminopropyl]methylamine, monoethanolamine, dimethylamine, isopropylamine, diglycolamine, potassium, and sodium salts, and combinations thereof.

In further embodiments, the composition comprises 2,4-D, or an agriculturally acceptable salt or ester thereof. In another embodiment, the composition comprises a 2,4-D salt selected from the group consisting of choline, dimethylamine, and isopropylamine salts, and combinations thereof. In another embodiment, the composition comprises a 2,4-D ester such as 2,4-DB.

In further embodiments, the composition comprises a monocarboxylate salt.

In further embodiments, the herbicidal composition concentrate comprises a C₁-C₆-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₅-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₄-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises a C₁-C₃-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises acetic acid, or an agriculturally acceptable salt thereof. In other embodiments, the herbicidal composition concentrate comprises formic acid, or an agriculturally acceptable salt thereof.

In further embodiments, the monocarboxylate salt or acetate salt is a non-ammoniated salt. In another embodiment, the monocarboxylate salt or acetate salt is an alkali metal salt. In another embodiment, the monocarboxylate salt or acetate salt is a potassium salt. In another embodiment, the monocarboxylate salt or acetate salt is a sodium salt.

In further embodiments, the composition further comprises a buffer.

In further embodiments, the herbicidal composition concentrate further comprises an alkali metal phosphate, such as dipotassium phosphate.

In further embodiments, the composition is an aqueous herbicidal composition.

In further embodiments, the composition further comprises a non-auxin herbicide.

In another embodiment, the non-auxin herbicide is selected from the group consisting of acetochlor, glyphosate, glufosinate, flumioxazin, fomesafen, and agriculturally acceptable salts thereof. In another embodiment, the non-auxin herbicide is glyphosate, or an agriculturally acceptable salt thereof. In another embodiment, the concentrate comprises a glyphosate salt selected from the group consisting of ammonium, diammonium, dimethylammonium, monoethanolamine, isopropylamine, and potassium salts, and combinations thereof. In another embodiment, the concentrate comprising a non-auxin herbicide satisfies one or more of the following conditions:

the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 1 gram (acid equivalent weight)/L to about 50 grams (acid equivalent weight)/L;

the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.

3. Illustrative Composition Embodiments Dicamba Concentrate

Compositions of particular interest include herbicidal compositions comprising dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and, optionally, glyphosate, or an agriculturally acceptable salt thereof.

One embodiment of the invention is directed to a herbicidal composition concentrate comprising:

dicamba, or an agriculturally acceptable salt or ester thereof; and

acetic acid, or an agriculturally acceptable salt thereof;

wherein the molar ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 10:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the acid equivalent weight ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 5:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentrate contains an amount of the acetic acid, or agriculturally acceptable salt thereof, from about 0.25% to about 25% by weight of the concentrate.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentration of the acetic acid, or agriculturally acceptable salt thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams

(acid equivalent weight)/L.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L; and

wherein the acid equivalent weight ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 5:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof; and

(b) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentrate comprises an amount of the acetic acid, or agriculturally acceptable salt thereof, sufficient to reduce the concentration of volatilized dicamba, or agriculturally acceptable salt or ester thereof, in the vapor phase surrounding the concentrate by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% relative to the concentration of volatilized dicamba, or agriculturally acceptable salt or ester thereof, in the vapor phase surrounding an otherwise identical concentrate lacking the acetic acid, or agriculturally acceptable salt thereof.

In further embodiments, the herbicidal composition concentrate comprises a dicamba salt selected from the group consisting of N,N-bis-[aminopropyl]methylamine, monoethanolamine, dimethylamine, isopropylamine, diglycolamine, potassium, and sodium salts, and combinations thereof.

In further embodiments, the herbicidal composition concentrate comprises an acetate salt. In another embodiment, the acetate salt is an alkali metal salt. In another embodiment, the acetate salt is a potassium salt. In another embodiment, the acetate salt is a sodium salt.

In further embodiments, the herbicidal composition concentrate further comprises a buffer.

In further embodiments, the herbicidal composition concentrate further comprises an alkali metal phosphate, such as dipotassium phosphate.

In further embodiments, the herbicidal composition concentrate is a dry powder herbicidal composition.

In further embodiments, the herbicidal composition concentrate is an aqueous herbicidal composition.

In further embodiments, the herbicidal composition concentrate further comprises a non-auxin herbicide. In another embodiment, the non-auxin herbicide is selected from the group consisting of acetochlor, glyphosate, glufosinate, flumioxazin, fomesafen, and agriculturally acceptable salts thereof. In another embodiment, the concentrate comprising a non-auxin herbicide satisfies one or more of the following conditions:

the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L;

the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.

4. Illustrative Composition Embodiments Dicamba/Glyphosate Concentrate

One embodiment of the invention is directed to a herbicidal composition concentrate comprising:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the molar ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 10:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the acid equivalent weight ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 5:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentrate contains an amount of the acetic acid, or agriculturally acceptable salt thereof, from about 0.25% to about 25% by weight of the concentrate.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentration of the acetic acid, or agriculturally acceptable salt thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the sum of the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, and the concentration of glyphosate, or an agriculturally acceptable salt thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L. In another embodiment, the sum of the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, and the concentration of glyphosate, or an agriculturally acceptable salt thereof, is from about 360 grams (acid equivalent weight)/L to about 480 grams (acid equivalent weight)/L.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the sum of the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, and the concentration of glyphosate, or an agriculturally acceptable salt thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L; and

wherein the acid equivalent weight ratio of dicamba, or an agriculturally acceptable salt or ester thereof, to glyphosate, or an agriculturally acceptable salt thereof, is from about 1:5 to about 2:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the sum of the concentration of dicamba, or an agriculturally acceptable salt or ester thereof, and the concentration of glyphosate, or an agriculturally acceptable salt thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L;

wherein the acid equivalent weight ratio of dicamba, or an agriculturally acceptable salt or ester thereof, to glyphosate, or an agriculturally acceptable salt thereof, is from about 1:5 to about 2:1; and

wherein the acid equivalent weight ratio of acetic acid, or agriculturally acceptable salt thereof, to dicamba, or agriculturally acceptable salt or ester thereof, is from about 1:10 to about 5:1.

In another embodiment, the herbicidal composition concentrate comprises:

(a) dicamba, or an agriculturally acceptable salt or ester thereof;

(b) glyphosate, or an agriculturally acceptable salt thereof; and

(c) acetic acid, or an agriculturally acceptable salt thereof;

wherein the concentrate comprises an amount of the acetic acid, or agriculturally acceptable salt thereof, sufficient to reduce the concentration of volatilized dicamba, or agriculturally acceptable salt or ester thereof, in the vapor phase surrounding the concentrate by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% relative to the concentration of volatilized dicamba, or agriculturally acceptable salt or ester thereof, in the vapor phase surrounding an otherwise identical concentrate lacking the acetic acid, or agriculturally acceptable salt thereof.

In further embodiments, the herbicidal composition concentrate comprises a dicamba salt selected from the group consisting of N,N-bis-[aminopropyl]methylamine, monoethanolamine, dimethylamine, isopropylamine, diglycolamine, potassium, and sodium salts, and combinations thereof.

In further embodiments, the herbicidal composition concentrate comprises an acetate salt. In another embodiment, the acetate salt is an alkali metal salt. In another embodiment, the acetate salt is a potassium salt. In another embodiment, the acetate salt is a sodium salt.

In further embodiments, the herbicidal composition concentrate further comprises a buffer.

In further embodiments, the herbicidal composition concentrate further comprises an alkali metal phosphate, such as dipotassium phosphate.

In further embodiments, the herbicidal composition concentrate is a dry powder herbicidal composition.

In further embodiments, the herbicidal composition concentrate is an aqueous herbicidal composition.

In another embodiment, the concentrate comprises a glyphosate salt selected from the group consisting of ammonium, diammonium, dimethylammonium, monoethanolamine, isopropylamine, and potassium salts, and combinations thereof.

In another embodiment, the concentrate satisfies one or more of the following conditions:

the sum of the concentration of dicamba, or agriculturally acceptable salt thereof, and the concentration of glyphosate, or agriculturally acceptable salt thereof, is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L;

the acid equivalent weight ratio of dicamba, or agriculturally acceptable salt thereof, to glyphosate, or agriculturally acceptable salt thereof, is from about 1:5 to about 2:1; and

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to dicamba, or agriculturally acceptable salt thereof, is from about 1:10 to about 5:1.

5. Illustrative Composition Embodiments Dicamba Application Mixture

In further embodiments, the herbicidal compositions correspond to the compositions described above in the “Illustrative Composition Embodiment (Application Mixture)” section wherein the auxin herbicide is dicamba, or an agriculturally acceptable salt or ester thereof.

6. Illustrative Composition Embodiments Dicamba/Glyphosate Application Mixture

In further embodiments, the herbicidal compositions correspond to the compositions described above in the “Illustrative Composition Embodiment (Application Mixture)” section wherein the auxin herbicide is dicamba, or an agriculturally acceptable salt or ester thereof, and the compositions further comprise glyphosate, or an agriculturally acceptable salt or ester thereof.

7. Illustrative Composition Embodiments 2,4-D

Compositions of particular interest also include herbicidal compositions comprising 2,4-D, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and, optionally, glyphosate, or an agriculturally acceptable salt thereof.

In further embodiments, the herbicidal compositions correspond to the compositions described above in the “Illustrative Composition Embodiment (Dicamba Concentrate),” “Illustrative Composition Embodiment (Dicamba/Glyphosate Concentrate),” “Illustrative Composition Embodiment (Dicamba Application Mixture),” and “Illustrative Composition Embodiment (Dicamba/Glyphosate Application Mixture)” sections except that the dicamba, or agriculturally acceptable salt or ester thereof, is replaced with 2,4-D, or an agriculturally acceptable salt or ester thereof.

H. HERBICIDAL COMPOSITION ADJUVANT

As discussed in more detail later, in certain embodiments the methods of controlling the growth of auxin-susceptible plants involve the preparation of an application mixture by combining a source of auxin herbicide (e.g., CLARITY®); a source of monocarboxylic acid, or a monocarboxylate thereof; an optional source of non-auxin herbicide (e.g., DURANGO® or POWERMAX®); and water. Another embodiment of the present invention, therefore, is directed to a herbicidal adjuvant composition comprising a monocarboxylic acid, or monocarboxylate thereof, and, optionally, an alkali metal phosphate, that can serve as the source of monocarboxylic acid, or a monocarboxylate thereof, used in the preparation of the application mixture.

In one embodiment, the adjuvant composition for use in the preparation of the herbicidal composition application mixture comprises:

(a) at least one monocarboxylic acid, or a monocarboxylate thereof; and

(b) an alkali metal phosphate;

wherein the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to alkali metal phosphate is from about 1:5 to about 5:1.

In various embodiments, the adjuvant composition comprises a C₁-C₆-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the adjuvant composition comprises a C₁-C₅-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the adjuvant composition comprises a C₁-C₄alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the adjuvant composition comprises a C₁-C₃-alkanoic acid, or an agriculturally acceptable salt thereof. In other embodiments, the adjuvant composition comprises acetic acid, or an agriculturally acceptable salt thereof. In other embodiments, the adjuvant composition comprises formic acid, or an agriculturally acceptable salt thereof.

In another embodiment, the adjuvant composition for use in the preparation of the herbicidal composition application mixture comprises:

(a) at least one monocarboxylic acid, or a monocarboxylate thereof; and

(b) an alkali metal phosphate;

wherein the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to alkali metal phosphate is from about 1:5 to about 5:1; and

wherein the composition contains an amount of the monocarboxylic acid, or monocarboxylate thereof, from about 2% to about 40% by weight of the composition.

In another embodiment, the adjuvant composition for use in the preparation of the aqueous herbicidal application mixture comprises:

(a) acetic acid, or an agriculturally acceptable salt thereof; and

(b) an alkali metal phosphate;

wherein the molar ratio of acetic acid, or agriculturally acceptable salt thereof, to alkali metal phosphate is from about 1:5 to about 5:1.

In another embodiment, the adjuvant composition for use in the preparation of the aqueous herbicidal application mixture comprises:

(a) acetic acid, or an agriculturally acceptable salt thereof; and

(b) an alkali metal phosphate;

wherein the molar ratio of acetic acid, or agriculturally acceptable salt thereof, to alkali metal phosphate is from about 1:5 to about 5:1; and

wherein the composition contains an amount of the acetic acid, or agriculturally acceptable salt thereof, from about 2% to about 40% by weight of the composition.

In various embodiments of the adjuvant composition, the composition is a dry powder composition.

In various embodiments of the adjuvant composition, the composition is a liquid composition, particularly an aqueous composition.

In various embodiments of the adjuvant composition, the composition comprises a non-ammoniated monocarboxylate or acetate salt. In other embodiments, the salt is an alkali metal salt, such as an alkali metal salt. In other embodiments, the salt is a potassium salt or a sodium salt, such as potassium acetate and sodium acetate.

In various embodiments of the adjuvant composition, the alkali metal phosphate is dipotassium phosphate.

In various embodiments of the adjuvant composition, the composition comprises potassium acetate and dipotassium phosphate.

I. METHODS OF REDUCING THE VOLATILITY OF AN AUXIN HERBICIDE

Another embodiment of the present invention is directed to a method of reducing the volatility of an auxin herbicide. The method generally comprises the step of contacting an auxin herbicide with a volatility-lowering effective amount of a monocarboxylic acid, or a monocarboxylate thereof, thereby reducing the volatility of the auxin herbicide.

In one embodiment, the contacting step satisfies at least one of the following conditions:

the molar ratio of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is from about 1:10 to about 5:1; and

the amount of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95% relative to the concentration of volatilized auxin herbicide in the vapor phase for an auxin herbicide in the absence of the monocarboxylic acid, or monocarboxylate thereof.

Volatilization can be measured by conventional means known to those skilled in the art. In one such method, for example, a gas stream is passed over an auxin herbicide composition and the auxin herbicide volatilizes from the composition into the gas stream which is then quantitatively analyzed for auxin herbicide content by methods known in the art. In another method, an auxin herbicide composition is distilled and the distillation condensate and/or distilled composition is analyzed for auxin herbicide content. In still another method, auxin herbicide volatilization is qualitatively assessed in a plant response study on a chosen sensitive species which will be clear to one of skill in the art.

It is believed that the addition of the monocarboxylic acid, or monocarboxylate thereof, at the loading values discussed above to the herbicidal compositions of the present invention effectively reduces auxin herbicide volatility and the associated crop injury without significantly reducing auxin herbicide effectiveness.

In one embodiment, no reduction in auxin herbicide effectiveness is observed for a herbicidal composition of the present invention relative to a reference composition lacking the monocarboxylic acid, or monocarboxylate thereof, but otherwise having the same composition.

In another embodiment, the auxin herbicide effectiveness of a herbicidal composition of the present invention is at least about 80%, 85%, 90%, 95%, or 99% of the auxin herbicide effectiveness of a reference composition lacking the monocarboxylic acid, or monocarboxylate thereof, but otherwise having the same composition.

In another embodiment, a reduced rate of crop injury is observed for a herbicidal composition of the present invention relative to a reference composition lacking the monocarboxylic acid, or monocarboxylate thereof, but otherwise having the same composition.

In another embodiment, the rate of crop injury associated with a herbicidal composition of the present invention is less than about 90%, 80%, 70%, 60%, or 50% of the crop injury associated with a reference composition lacking the monocarboxylic acid, or monocarboxylate thereof, but otherwise having the same composition.

In another embodiment, a reduction in the rate of crop injury and no reduction in auxin herbicide effectiveness are observed for the herbicidal compositions of the present invention relative to a reference composition lacking the monocarboxylic acid, or monocarboxylate thereof, but otherwise having the same composition.

In another embodiment, the herbicidal composition loading of the monocarboxylic acid, or monocarboxylate thereof, is sufficient to provide both commercially acceptable weed control and a commercially acceptable rate of crop injury.

A “commercially acceptable rate of weed control” varies with the weed species, degree of infestation, environmental conditions, and the associated crop plant. Typically, commercially effective weed control is defined as least about 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or even greater than 95%. Although it is generally preferable from a commercial viewpoint that 80-85% or more of the weeds be destroyed, commercially significant weed control can occur at much lower levels, particularly with some very noxious, herbicide-resistant plants. “Weed control,” as used herein, refers to any observable measure of control of plant growth, which can include one or more of the actions of (1) killing, (2) inhibiting growth, reproduction or proliferation, and (3) removing, destroying, or otherwise diminishing the occurrence and activity of plants. Weed control can be measured by any of the various methods known in the art. For example, weed control can be determined as a percentage as compared to untreated plants following a standard procedure wherein a visual assessment of plant mortality and growth reduction is made by one skilled in the art specially trained to make such assessments. In another control measurement method, control is defined as an average plant weight reduction percentage between treated and untreated plants. Preferably, commercial weed control is achieved at no greater than 30 days after treatment (DAT), such as from 18 to 30 DAT.

A “commercially acceptable rate of crop injury” for the present invention likewise varies with the crop plant species. Typically, a commercially acceptable rate of crop injury is defined less than about 20%, 15%, 10% or even less than about 5%. Crop damage can be measured by any means known in the art, such as those describe above for weed control determination. Preferably, crop damage appears no more than from 10% to 20% at no greater than 30 DAT, such as from 3 to 21 or from 3 to 30 DAT.

J. METHODS OF CONTROLLING GROWTH OF AUXIN-SUSCEPTIBLE PLANTS

Another embodiment of the present invention is directed to methods of controlling the growth of auxin-susceptible plants, particularly those growing in and/or adjacent to a field of crop plants. The methods generally comprise applying to the auxin-susceptible plants an aqueous herbicidal composition mixture comprising at least one auxin herbicide; at least one monocarboxylic acid, or monocarboxylate thereof; and, optionally, a non-auxin herbicide; wherein the application mixture exhibits reduced auxin herbicide volatility relative to an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.

The aqueous herbicidal composition mixture applied to the auxin-susceptible plants can be provided, for example, in the following manner:

(a) as a ready-to-use aqueous herbicidal composition that can be applied without the need for further dilution with water or other preparation;

(b) as a herbicidal composition application mixture prepared by diluting with water any of the herbicidal composition concentrates within in the scope of the present disclosure;

(c) as a herbicidal composition application mixture prepared by combining two or more separate components with water (e.g., a tank mix);

(d) as a herbicidal composition application mixture prepared by introducing separate feed streams to a spraying or application system so that the feed streams are co-mixed immediately prior to use; or

(e) in any other manner reasonably adapted to apply to auxin-susceptible plants a herbicidal composition comprising the auxin herbicide in admixture with the monocarboxylic acid, or monocarboxylate thereof.

In one embodiment, the methods of controlling the growth of auxin-susceptible plants comprise the steps of:

(a) preparing an aqueous herbicidal application mixture by diluting with water a herbicidal composition concentrate of any of the herbicidal composition concentrates disclosed in this application; and

(b) applying a herbicidally effective amount of the application mixture to the auxin-susceptible plants.

In another embodiment, the preparing step does not comprise separately introducing a pH-lowering agent (e.g., an acidifying agent) with the concentrate and water during the preparation of the application mixture; wherein the pH-lowering agent is one that is capable of lowering the pH of the application mixture in the absence of any buffering provided by other components of the application mixture.

In one embodiment, the methods of controlling the growth of auxin-susceptible plants comprise the steps of:

(a) combining a source of auxin herbicide; a source of monocarboxylic acid, or a monocarboxylate thereof; and water to prepare an aqueous herbicidal application mixture; and

(b) applying a herbicidally effective amount of the application mixture to the auxin-susceptible plants;

wherein the application mixture satisfies one or more of the following conditions:

the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1;

the composition contains an amount of the monocarboxylic acid, or

monocarboxylate thereof, from about 0.1% to about 25% by weight of the composition;

the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and

the application mixture comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the application mixture by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.

In another embodiment, the methods of controlling the growth of auxin-susceptible plants comprise the steps of:

(a) combining a source of auxin herbicide; a source of non-auxin herbicide, or agriculturally acceptable salt thereof; a source of monocarboxylic acid, or a monocarboxylate thereof; and water to prepare an aqueous herbicidal application mixture; and

(b) applying a herbicidally effective amount of the application mixture to the auxin-susceptible plants;

wherein the application mixture satisfies one or more of the following conditions:

the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1;

the composition contains an amount of the monocarboxylic acid, or

monocarboxylate thereof, from about 0.1% to about 25% by weight of the composition;

the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and

the application mixture comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the application mixture by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.

When the methods of controlling the growth of auxin-susceptible plants involve the use of a herbicidal composition application mixture comprising a non-auxin herbicide, the application mixture generally satisfies one or more of the following conditions:

the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 1 gram (acid equivalent weight)/L to about 50 grams (acid equivalent weight)/L;

the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the application mixture comprises a non-auxin herbicide is selected from the group consisting of acetochlor, glyphosate, glufosinate, flumioxazin, fomesafen, and agriculturally acceptable salts thereof. In one embodiment, the application mixture comprises glyphosate, or an agriculturally acceptable salt thereof.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the auxin herbicide is selected from the group consisting of dicamba, or an agriculturally acceptable salt or ester thereof, and 2,4-D, or an agriculturally acceptable salt or ester thereof.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the auxin herbicide is dicamba, or an agriculturally acceptable salt or ester thereof.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the auxin herbicide is 2,4-D, or an agriculturally acceptable salt or ester thereof.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the application mixture comprises a monocarboxylate salt.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the application mixture comprises acetic acid, or an agriculturally acceptable salt thereof.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the monocarboxylate or acetate salt is a non-ammoniated salt. In still other embodiments, the salt is an alkali metal salt. In still other embodiments, the salt is a potassium salt. In still other embodiments, the salt is a sodium salt.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the application mixture further comprises a buffer.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the application mixture further comprises an alkali metal phosphate, such as dipotassium phosphate.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants, the combining step does not comprise separately introducing a pH-lowering agent with the source of auxin herbicide; the source of monocarboxylic acid, or monocarboxylate thereof; and water during the preparation of the application mixture; wherein the pH-lowering agent is one that is capable of lowering the pH of the application mixture in the absence of any buffering provided by other components of the application mixture.

In various embodiments of the described methods of controlling the growth of auxin-susceptible plants wherein the application mixture comprises a non-auxin herbicide, the combining step does not comprise separately introducing a pH-lowering agent with the source of auxin herbicide; the source of non-auxin herbicide; the source of monocarboxylic acid, or monocarboxylate thereof; and water during the preparation of the application mixture; wherein the pH-lowering agent is one that is capable of lowering the pH of the application mixture in the absence of any buffering provided by other components of the application mixture.

In the described methods, the application mixture is applied to the auxin-susceptible plants at an application rate sufficient to give a commercially acceptable rate of weed control. The appropriate application rate for the application mixture can be readily determined by one of skill in the art and is usually expressed as amount of auxin herbicide per unit area treated, e.g., grams acid equivalent per hectare (g a.e./ha). Depending on the plant species and growing conditions, the period of time required to achieve a commercially acceptable rate of weed control can be as short as a week or as long as three weeks, four weeks, or one month. Typically, a period of about two to three weeks is needed for the auxin herbicide to exert its full effect.

The timing of application can vary. The application mixture can be applied, for example, pre-planting of the crop plant, such as from about two to about three weeks before planting auxin-susceptible crop plants or crop plants not having a auxin herbicide-resistant trait. Crop plants that are not susceptible to certain auxin herbicides (such as corn or plants having an auxin herbicide-resistant trait), however, generally have no pre-planting restriction and the application mixture can be applied immediately before planting such crops.

The auxin-susceptible plants can be weeds or crop plants. Crop plants include, for example, vegetable crops, grain crops, flowers, and root crops. Crop plants further encompass hybrids, inbreds, and transgenic or genetically modified plants.

In some embodiments, the crop plants are auxin tolerant species that are not susceptible to auxin herbicides or are a transgenic species that contain an auxin (e.g., dicamba) resistant trait. Examples include dicamba resistant corn, cotton or soybean. Dicamba resistant crops can further comprise one or more additional traits including, without limitation: herbicide resistance (e.g., resistance to other auxin herbicides (e.g., 2,4-D or fluoroxypyr), glyphosate, glufosinate, acetolactate synthase inhibitor herbicides (e.g., imazamox, imazethapyr, imazaquin and imazapic), acetyl CoA carboxylase inhibitors (e.g., sethoxydim and clethodim), etc.); insect resistance such as Bacillus thuringiensis (Bt); high oil; high lysine; high starch; nutritional density; and/or drought resistance.

In some embodiments, the weeds and/or crop plants are glyphosate tolerant or contain a glyphosate resistant trait. Examples include glyphosate resistant corn, cotton or soybean.

In some embodiments, the crop plants comprise stacked traits such as dicamba and glyphosate resistance; dicamba and glufosinate resistance; dicamba and acetolactate synthase (ALS) or acetohydroxy acid synthase (AHAS) resistance; dicamba, glyphosate and glufosinate resistance; dicamba, glyphosate and ALS or AHAS resistance; dicamba, glufosinate and ALS or AHAS resistance; or dicamba, glyphosate, glufosinate and ALS or AHAS resistance.

In some embodiments, the plants can additionally include other herbicide, insect and disease resistance traits, as well as combinations of those traits. For instance, the plants can have dicamba, 2,4-D, or fluoroxypyr resistant traits.

K. METHODS OF CONTROLLING OFF-SITE MOVEMENT

Another embodiment of the present invention is directed to a method of controlling off-site movement of an auxin herbicide by contacting the auxin herbicide with a volatility-lowering effective amount of a monocarboxylic acid, or a monocarboxylate thereof, prior to application of the auxin herbicide.

In one embodiment, the method comprises the steps of:

(a) preparing an aqueous herbicidal application mixture comprising an auxin herbicide; a monocarboxylic acid, or a monocarboxylate thereof; water; and, optionally, a source of non-auxin herbicide; and

(b) applying a herbicidally effective amount of the application mixture to auxin-susceptible plants;

wherein the application mixture satisfies one or more of the following conditions:

the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1;

the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1;

the composition contains an amount of the monocarboxylic acid, or monocarboxylate thereof, from about 0.1% to about 25% by weight of the composition;

the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and

the application mixture comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the application mixture by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.

L. METHODS OF COUNSELING ON USE OF AN AUXIN HERBICIDE

Another embodiment of the present invention is directed to methods of counseling an individual regarding the preparation and/or application of an auxin herbicide.

In one embodiment, the invention is directed to a method of counseling an individual on the application of an auxin herbicide to auxin-susceptible plants, the method comprising:

(a) identifying a source of an auxin herbicide;

(b) instructing the individual to prepare an aqueous herbicidal composition application mixture from the source of auxin herbicide; and

(c) additionally instructing the individual to supplement the application mixture with a monocarboxylic acid, or monocarboxylate thereof, prior to the application of the application mixture to auxin-susceptible plants.

In another embodiment, the invention is directed to a method of counseling an individual on the application of an auxin herbicide to auxin-susceptible plants, the method comprising:

(a) identifying a source of an auxin herbicide;

(b) identifying a source of a monocarboxylic acid, or a monocarboxylate thereof; and

(c) instructing the individual to prepare an aqueous herbicidal composition application mixture from the source of auxin herbicide and the source of monocarboxylic acid, or monocarboxylate thereof, for application to the auxin-susceptible plants.

The source of monocarboxylic acid, or a monocarboxylate thereof, can be, for example, a single source such as the herbicidal composition adjuvant previously discussed, or even a source that provides for in situ formation of the monocarboxylic acid, or monocarboxylate thereof, in the herbicidal composition application mixture.

Having described the invention in detail, it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims.

M. EXAMPLES

The following non-limiting examples are provided to further illustrate the present invention.

Example 1 Compositions

The herbicidal tank mix compositions listed in the tables below were prepared using CLARITY® (DGA dicamba from BASF), ROUNDUP POWERMAX® (potassium glyphosate from Monsanto), BANVEL® (DMA dicamba from BASF), DURANGO® DMA® (DMA glyphosate'e from Dow AgroSciences) and/or 2,4-D amine (Albaugh) by successively adding each specified herbicide to water and mixing. Those tank mix formulations containing additional tank mix adjuvants such as potassium acetate (Sigma), dipotassium phosphate (ICL), and/or ammonium sulfate (Sigma) were typically prepared by adding aqueous stock solutions of the adjuvants to the herbicide mixture.

Herbicide salts not purchased from a commercial vendor, such as IPA glyphosate and MEA dicamba, typically were prepared by mixing the herbicide acid with the desired amine. The herbicide acid to amine ratio typically is about 1:1. In certain instances, a slight excess of amine is desired. As used in these examples, DGA refers to diglycolamine; DMA refers to dimethylamine; IPA refers to isopropylamine; and MEA refers to monoethanolamine.

Herbicidal tank mix compositions prepared by the method described above are listed in Tables 1-1 through 1-15 below:

TABLE 1-1 (Composition 854-B) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 30.00 3.00% 1.20% ae ROUNDUP POWERMAX ® 60.60 6.06% 2.40% ae water 909.78

TABLE 1-2 (Composition 854-C) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 30.03 3.00% 1.20% ae ROUNDUP POWERMAX ® 60.34 6.03% 2.40% ae dipotassium phosphate (50%) 40.02 4.00% 2.00% water 869.74

TABLE 1-3 (Composition 854-F) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 7.50 3.00% 1.20% ae ROUNDUP POWERMAX ® 15.14 6.06% 2.40% ae potassium acetate 5.04 2.01% 2.01% Water 222.42

TABLE 1-4 (Composition 751-E) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 7.51 3.00% 1.20% ae ROUNDUP POWERMAX ® 15.16 6.06% 2.40% ae ammonium sulfate (AMS) 7.35 2.94% 1.00% water 220.07

TABLE 1-5 (Composition 751-D) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 7.49 3.00% 1.20% ae ROUNDUP POWERMAX ® 15.10 6.06% 2.40% ae potassium acetate (50%) 10.00 4.00% 2.00% ammonium sulfate (34%) 7.34 2.94% 1.00% water 210.07

TABLE 1-6 (Composition 210-D) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 7.48 3.00% 1.20% ae ROUNDUP POWERMAX ® 14.99 6.00% 2.40% ae 1:1 wt/wt 50% potassium acetate/50% 10.00 4.00% 2.00% dipotassium phosphate water 217.42

TABLE 1-7 (Composition 870-A) INGREDIENT WT (g) WT % % ACTIVE DMA glyphosate (DURANGO ® 15.04 6.02% 2.40% ae DMA ®) 2,4-D amine 15.50 6.20% 2.40% ae water 219.54

TABLE 1-8 (Composition 870-B) INGREDIENT WT (g) WT % % ACTIVE DMA glyphosate (DURANGO ® 15.04 6.02% 2.40% ae DMA ®) 2,4-D amine 15.43 6.17% 2.40% ae potassium acetate (50%) 10.02 4.00% 2.00% water 209.57

TABLE 1-9 (Composition 870-C) INGREDIENT WT (g) WT % % ACTIVE IPA glyphosate 19.54 7.82% 2.40% ae (30.8% ae) 2,4-D amine 15.42 6.17% 2.40% ae potassium acetate (50%) 10.00 4.00% 2.00% water 205.04

TABLE 1-10 (Composition 870-D) INGREDIENT WT (g) WT % % ACTIVE IPA glyphosate (30.8%) 19.54 7.82 2.40% ae 2,4-D amine 15.42 6.17 2.40% ae water 215.04

TABLE 1-11 (Composition 563-2) INGREDIENT WT (g) WT % % ACTIVE BANVEL ® 7.34 2.94% 1.20% ae ROUNDUP POWERMAX ® 15.00 6.00% 2.40% ae water 227.66

TABLE 1-12 (Composition 563-5) INGREDIENT WT (g) WT % % ACTIVE BANVEL ® 7.34 2.94% 1.20% ae ROUNDUP POWERMAX ® 15.07 6.00% 2.40% ae potassium acetate (50%) 10.05 4.00% 2.00% water 217.65

TABLE 1-13 (Composition 563-1) INGREDIENT WT (g) WT % % ACTIVE MEA dicamba (62.2%) 4.81 1.93% 1.20% ae ROUNDUP POWERMAX ® 15.00 6.00% 2.40% ae water 230.18

TABLE 1-14 (Composition 563-4) INGREDIENT WT (g) WT % % ACTIVE MEA dicamba (62.2%) 4.85 1.93% 1.20% ae ROUNDUP POWERMAX ® 14.96 6.00 2.40% ae potassium acetate (50%) 10.03 4.00%   2% water 220.18

TABLE 1-15 (Composition 836-1) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.01 3.0 1.2% ae ROUNDUP POWERMAX ® 12.05 6.1 2.4% ae water 181.98

For the tank mix compositions in Table 1-16 through Table 1-19, the monocarboxylic acid salt (e.g., potassium acetate) was formed in situ by combining a monocarboxylic acid with a neutralizing base. The compositions were prepared by mixing the herbicide(s) with water followed by addition of the monocarboxylic acid followed by addition of the neutralizing base. Although a specific order of addition of the ingredients is not required to prepare the final composition, the order of addition described above can be advantageous to reduce the heat generation resulting when the ingredients are combined. The neutralizing base (potassium hydroxide in the compositions below) was added as a 45% w/w aqueous solution.

TABLE 1-16 (Composition 836-2) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.00 3.0 1.2% ae ROUNDUP POWERMAX ® 12.04 6.0 2.4% ae succinic acid 2.57 1.3 potassium hydroxide 5.46 (45% solution) water 174.01

TABLE 1-17 (Composition 836-3) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.00 3.0 1.2% ae ROUNDUP POWERMAX ® 12.09 6.0 2.4% ae propionic acid 1.63 0.8 potassium hydroxide 2.72 (45% solution) water 177.65

TABLE 1-18 (Composition 836-4) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.01 3.0 1.2% ae ROUNDUP POWERMAX ® 12.03 6.0 2.4% ae acetic acid 1.32 0.7 potassium hydroxide 2.73 (45% solution) water 177.98

TABLE 1-19 (Composition 836-5) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.05 3.0 1.2% ae ROUNDUP POWERMAX ® 12.03 6.0 2.4% ae formic acid 1.00 0.5 potassium hydroxide 2.73 (45% solution) water 178.32

TABLE 1-20 (Composition 836-6) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 6.01 3.0 1.2% ae ROUNDUP POWERMAX ® 12.03 6.0 2.4% ae potassium hydroxide 1.78 0.9 (45% solution) water 180.19

TABLE 1-21 (Composition 893-A) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.50 3.0 1.2% ae ROUNDUP POWERMAX ® 15.20 6.0 2.4% ae water 227.46

TABLE 1-22 (Composition 893-B) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.50 3.0 1.2% ae ROUNDUP POWERMAX ® 15.04 6.0 2.4% ae potassium acetate 10.04 2.0% ai (50% solution) water 217.44

TABLE 1-23 (Composition 893-C) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.67 3.0 1.2% ae ROUNDUP POWERMAX ® 15.02 6.0 2.4% ae potassium formate 5.05 2.0% ai water 222.46

TABLE 1-24 (Composition 893-D) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.51 3.0 1.2% ae ROUNDUP POWERMAX ® 15.03 6.0 2.4% ae potassium benzoate 5.05 2.0% ai water 222.45

TABLE 1-25 (Composition 893-F) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.51 3.0 1.2% ae ROUNDUP POWERMAX ® 15.04 6.0 2.4% ae sodium acetate 5.01 2.0% ai water 222.44

TABLE 1-26 (Composition 854-A) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 30.0 3.0 1.2% ae water

TABLE 1-27 (Composition 854-D) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.5 3.0 1.2 ae ROUNDUP POWERMAX ® 15.08 6.0 2.4 ae potassium oxalate (25% solution) 20.0 8.0 2.0 ai water 207.42

TABLE 1-28 (Composition 854-E) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 7.5 3.0 1.2 ae ROUNDUP POWERMAX ® 15.08 6.0 2.4 ae potassium citrate (50%) 10.0 4.0 water 217.42

The potassium acetate used in the compositions in Tables 1-29 through Table 1-32 was prepared by adding the desired amount of glacial acetic acid to the desired amount of potassium hydroxide (45% w/w solution) in an ice bath without allowing the temperature of the solution to rise above 60° C. The pre-formed potassium acetate was then added to the solution containing the herbicide(s). The ratio indicated in the tables below is on a molar basis. For example, “50/50 AcOH/KOH” means a 1:1 M ratio of acetic acid to potassium hydroxide. The compositions in the tables below were prepared by adding the desired amount of each ingredient and stirring for about 20 minutes.

Alternatively, the monocarboxylic acid salt can be prepared by adding the monocarboxylic acid to the solution containing the herbicide(s) followed by addition of a neutralizing base. Although a specific order of addition of the ingredients is not required to prepare the final composition, the order of addition described above can be advantageous to reduce the heat generation resulting when the ingredients are combined.

TABLE 1-29 (Composition 503-1) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 157.4 78.7 31.0 50/50 AcOH/KOH 42.6 21.3  6.9 (AcOH)

TABLE 1-30 (Composition 503-3) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 157.4 78.7 31.0 60/40 AcOH/KOH 42.6 21.3  8.2 (AcOH)

TABLE 1-31 (Composition 295-3) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 112.3 56.2 31.0 60/40 AcOH/KOH 65.1 32.6 12.6 (AcOH) water 22.6 11.3

TABLE 1-32 (Composition 295-6) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 112.3 56.2 31.0 60/40 AcOH/KOH 86.8 43.4 16.8 (AcOH) water 0.9 0.4

TABLE 1-33 (Composition 771-C) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 29.15 62.94 acetic acid 6.26 6.26 potassium hydroxide 8.72 8.72 water 2.19 2.19

TABLE 1-34 (Composition 761-B) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 32.82 71.20 acetic acid 4.48 9.72 potassium hydroxide 6.24 13.53 water 2.56

Example 2 Compositions

Herbicidal compositions containing DGA dicamba and MEA glyphosate were prepared by mixing CLARITY® with MEA glyphosate with water. After stirring the mixture for 5 minutes, surfactants AGM550 and Agnique PG8107-G were added followed by ferric citrate (for mitigating necrosis in certain crops) and anti-foaming agent SAG 1572, and the mixture stirred for an additional 30 minutes. Premix compositions which also contain additional adjuvants, such as potassium acetate, were prepared as described above with the modification of replacing the water with the desired amount of aqueous adjuvant. The MEA glyphosate salt used in the preparation of the compositions was prepared by mixing glyphosate acid and 1.35 molar equivalents of MEA with water. The list of ingredients of the dicamba/glyphosate premix composition is set forth in Table 2-1.

TABLE 2-1 (DGA Dicamba/MEA Glyphosate Premix) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 32.36 32.36% 12.75% 1.35 MEA glyphosate (46.9%) 54.37 54.37% 25.50% AGM 550 2.50 2.50% Agnique PG8107-G 5.00 5.00% SAG 1572 0.01 0.01% Ferric citrate (7.0% Fe) 0.31 0.31% 0.02% water 5.44 5.44%

Dicamba/glyphosate premixes containing additional adjuvants, such as potassium acetate, typically were prepared by adding the desired amount of an aqueous solution of the adjuvant to the premix prepared as described in Tables 2-2 and 2-3 below.

TABLE 2-2 (Composition 751-F) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba/MEA glyphosate premix 23.51 9.40% 1.20% ae potassium acetate (50%) 10.00 4.00% 2.00% water 216.48

TABLE 2-3 (Composition 210-F) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba/MEA glyphosate premix 23.48 9.39% 2.40% ae 1:1 wt/wt 50% potassium acetate/50% 10.04 4.00% 2.00% dipotassium phosphate Water 216.51

TABLE 2-4 (Composition 210-E) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 32.2 32.12 12.75 1.35 MEA glyphosate (46.8%) 55.0 54.49 25.50 AGM 550 2.50 2.50 Agnique PG8107-G 5.1 5.00 SAG 1572 0.02 0.01 Ferric citrate (7.0% Fe) 0.33 0.31 0.02% 50% K acetate solution 5.7 5.7

The potassium acetate used in the formulations in Tables 2-5 through Table 2-13 was prepared by adding the desired amount of glacial acetic acid to the desired amount of potassium hydroxide (45% w/w solution) in an ice bath without allowing the temperature of the solution to rise above 60° C. The ratio indicated in the tables below is on a molar basis. For example “50/50 AcOH/KOH” means a 1:1 M ratio of acetic acid to potassium hydroxide. The compositions in the tables below were prepared by adding the desired amount of each ingredient and stirring for about 20 minutes. Alternatively, the monocarboxylic acid salt can be prepared by adding the monocarboxylic acid to the solution containing the herbicide(s) followed by addition of a neutralizing base.

The Fe dopant in Tables 2-8 through 2-13 (added to mitigate necrosis in certain crops) was prepared by mixing ferric sulfate and citric acid.

TABLE 2-5 (Composition 287-5) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (54.8% ae) 18.25 18.25 10.0 1.35 MEA glyphosate (46.9% ae) 42.74 42.74 20.0 SAG 1572 0.01 0.01 Ferric Citrate (7.0% Fe) 0.31 0.31 0.02 60/40 AcOH/KOH (38.7 AcOH) 6.98 6.98 2.70 water 31.72 31.72

TABLE 2-6 (Composition 287-6) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (54.8% ae) 17.34 17.34 9.50 1.35 MEA glyphosate (46.9% ae) 40.60 40.60 19.00 SAG 1572 0.01 0.01 Ferric Citrate (7.0% Fe) 0.31 0.31 0.02 60/40 AcOH/KOH (38.7 AcOH) 13.44 13.44 5.20 Water 28.30 28.30

TABLE 2-7 (Composition 512-1) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (CLARITY ®) 31.61 31.61 12.55 1.35 MEA glyphosate (46.9% ae) 53.63 53.63 25.10 AGM 550 2.50 2.50 AGNIQUE PG8107-G 5.00 5.00 SAG 1572 0.01 0.01 Ferric Citrate (7.0% Fe) 0.31 0.31 0.02 70/30 AcOH/KOH (38.7 AcOH) 6.93 6.93

TABLE 2-8 (Composition 248-1) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 18.03 18.03 9.95 1.35 MEA glyphosate (46.8% ae) 45.51 45.51 19.90 Ethoquad C12 75 DEG 3.49 3.49 SAG 1572 0.01 0.01 Fe Dopant (4.5% Fe) 0.49 0.49 0.02 60/40 AcOH/KOH (38.7 AcOH) 6.95 6.95 2.70 water 28.49 28.49

TABLE 2-9 (Composition 248-2) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 18.08 18.08 9.95 1.35 MEA glyphosate (46.8% ae) 42.62 42.62 19.90 Ethoquad C12 75 DEG 3.49 3.49 SAG 1572 0.02 0.02 Fe Dopant (4.5% Fe) 0.49 0.49 0.02 60/40 AcOH/KOH (38.7 AcOH) 10.86 10.86 4.20 Water 24.61 24.61

TABLE 2-10 (Composition 248-3) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 17.91 17.91 9.90 1.35 MEA glyphosate (46.8% ae) 42.28 42.28 19.80 Ethoquad C12 75 DEG 3.61 3.61 SAG 1572 0.02 0.02 Fe Dopant (4.5% Fe) 0.53 0.53 0.02 60/40 AcOH/KOH (38.7 AcOH) 13.95 13.95 5.40 water 21.81 21.81

TABLE 2-11 (Composition 249-1) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 18.00 18.00 9.95 1.35 MEA glyphosate (46.8% ae) 42.52 42.52 19.90 AGM 550 2.48 2.48 Agnique PG8107-G 1.95 1.95 SAG 1572 0.01 0.01 Fe Dopant (4.5% Fe) 0.60 0.60 0.02 60/40 AcOH/KOH (38.7 AcOH) 6.96 6.96 2.70 water 27.48 27.48

TABLE 2-12 (Composition 249-2) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 18.04 18.04 9.95 1.35 MEA glyphosate (46.8% ae) 42.50 42.50 19.90 AGM 550 2.50 2.50 Agnique PG8107-G 2.00 2.00 SAG 1572 0.01 0.01 Fe Dopant (4.5% Fe) 0.49 0.49 0.02 60/40 AcOH/KOH (38.7 AcOH) 10.83 10.83 4.20 water 23.59 23.59

TABLE 2-13 (Composition 249-3) INGREDIENT WT (g) WT % % ACTIVE DGA dicamba (55.2%) 17.93 17.93 9.90 1.35 MEA glyphosate (46.8% ae) 42.37 42.37 19.80 AGM 550 2.50 2.50 Agnique PG8107-G 1.97 1.97 SAG 1572 0.01 0.01 Fe Dopant (4.5% Fe) 0.49 0.49 0.02 60/40 AcOH/KOH (38.7 AcOH) 14.00 14.00 5.40 water 20.79 20.79

TABLE 2-14 (Composition 530-2) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® 125.63 25.13  9.90 ae 1.35 MEA glyphosate (46.8% ae) 211.54 42.31 19.80 ae AGM 550 12.50 2.50 Agnique PG8107-G 10.00 2.00 SAG 1572 0.05 0.01 Fe Dopant (4.5% Fe) 1.94 0.39 0.02 65/35 AcOH/KOH (38.7 AcOH) 64.29 12.86 5.40 water 199.68

TABLE 2-15 (Composition 540-1) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® (39.4% α.ε.) 124.37 24.87  9.80 ae 1.35 MEA glyphosate (46.8% ae) 209.40 41.88 19.60 ae Ethoquad C12 75 DEG 17.50 3.50 65/35 AcOH/KOH (42.0% AcOH) 64.29 12.86 5.40 Fe Dopant (4.5% Fe) 1.94 0.39 0.0175 SAG 1572 0.05 0.01 water 82.45 16.49

TABLE 2-16 (Composition 540-4) INGREDIENT WT (g) WT % % ACTIVE CLARITY ® (39.4% α.ε.) 123.10 24.62  9.70 ae 1.35 MEA glyphosate (46.8% ae) 207.26 41.45 19.40 ae AGM 550 12.50 2.50 Agnique PG8107-G 10.00 2.00 SAG 1572 0.05 0.01 Fe Dopant (4.5% Fe) 1.94 0.39 0.0175 60/40 AcOH/KOH (38.7% AcOH) 69.77 13.95 5.40 Phosphate ester 5.00 1.000 water 70.38 14.08

Example 3 Measurement of Dicamba Volatility (Humidome)

Humidomes obtained from Hummert International (Part Nos 14-3850-2 for humidomes and 11-3050-1 for 1020 flat tray) were modified by cutting a 2.2 cm diameter hole on one end approximately 5 cm from the top to allow for insertion of a glass air sampling tube (22 mm OD) containing a polyurethane foam (PUF) filter. The sampling tube was secured with a VITON o-ring on each side of the humidome wall. The air sampling tube external to the humidome was fitted with tubing that was connected to a vacuum manifold immediately prior to sampling.

The flat tray beneath the humidome was filled with 1 liter of sifted dry or wet 50/50 soil (50% Redi-Earth and 50% US 10 Field Soil) to a depth of about 1 cm. The flat tray bottom containing the dicamba formulation on soil was covered with the humidome lid and the lid was secured with clamps. The assembled humidomes were placed in a temperature and humidity controlled environment and connected to a vacuum manifold through the air sampling line. Air was drawn through the humidome and PUF at a rate of 2 liters per minute (LPM) for 24 hours at which point the air sampling was stopped. The humidomes were then removed from the controlled environment and the PUF filter was removed. The PUF filter was extracted with 20 mL of methanol and the solution was analyzed for dicamba concentration using LC-MS methods known in the art.

To measure the dicamba concentration in the gas phase (air) that volatilized from the spray solutions, compositions were prepared to contain 1.2% a.e. dicamba which is equivalent to an application rate of 1.0 lb/A a.e. at 10 gallons per acre (GPA). Where glyphosate was added or was part of the formulation, glyphosate was present at a concentration of 2.4% a.e. or 2.0 lb/A a.e. Where 2,4-D was added or was part of the formulation, 2,4-D was present at 2.4% ae or 2.0 lb/A ae at 10 gallons per acre (GPA). The growth chambers were set at 35° C. and 40% relative humidity (RH). For each composition four separate humidome boxes were sprayed to have 4 replicate measurements for each formulation. Table(s) 3-1 to 3-7 below provide the mean concentration of dicamba in air for each formulation. Where concentrations of dicamba were below the limits of detection, “nd” is indicated in the tables below.

Humidome Results:

TABLE 3-1 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 854-A 1.2% ae CLARITY ® 0.03 0.00 0.00 854-B 1.2% ae CLARITY ® + 0.44 0.11 0.06 2.4% ae POWERMAX ® 854-F 1.2% ae CLARITY ® + nd na na 2.4% ae POWERMAX ® + 2% potassium acetate 854-C 1.2% ae CLARITY ® + 0.06 0.01 0.01 2.4% ae POWERMAX ® + 2% dipotassium phosphate 854-D 1.2% ae CLARITY ® + 0.47 0.13 0.06 2.4% ae POWERMAX ® + 2% potassium oxalate 854-E 1.2% ae CLARITY ® + 0.33 0.20 0.10 2.4% ae POWERMAX ® + 2% potassium citrate

TABLE 3-2 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 854-A 1.2% ae CLARITY ® 0.02 0.00 0.00 854-B 1.2% ae CLARITY ® + 0.49 0.16 0.08 2.4% ae POWERMAX ® 731-C 1.2% ae CLARITY ® + nd na na 2.4% ae POWERMAX ® + 2% potassium acetate 854-C 1.2% ae CLARITY ® + 0.04 0.01 0.01 2.4% ae POWERMAX ® + 2% dipotassium phosphate

TABLE 3-3 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 751-A 1.2% ae CLARITY ® 0.02 0.00 0.00 751-B 1.2% ae CLARITY ® + 1.04 0.50 0.25 2.4% ae POWERMAX ® 751-E 1.2% ae CLARITY ® + 6.13 0.55 0.32 2.4% ae POWERMAX ® + 1% AMS 751-C 1.2% ae CLARITY ® + nd na na 2.4% ae PowerMAX + 2% potassium acetate 751-D 1.2% ae CLARITY ® + 3.63 0.77 0.38 2.4% ae POWERMAX ® + 2% potassium acetate + 1% ammonium sulfate

TABLE 3-4 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 210-A 1.2% ae CLARITY ® + 0.92 0.22 0.11 2.4% ae POWERMAX ® 210-B 1.2% ae Clarity + nd na na 2.4% ae POWERMAX ® + 2% potassium acetate 210-C 1.2% ae CLARITY ® + 0.16 0.02 0.01 2.4% ae POWERMAX ® + 2% potassium acetate + 1% ammonium sulfate 210-D 1.2% ae CLARITY ® + 0.01 0.00 0.00 2.4% ae POWERMAX ® + 2% potassium acetate/ dipotassium phosphate

TABLE 3-5 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 870-A 2.4% ae DURANGO ® 0.10 0.03 0.01 DMA ® + 2.4% 2,4-D amine 870-B 2.4% ae DURANGO ® 0.01 0.00 0.00 DMA ® + 2.4% 2,4-D amine + 2% potassium acetate 870-D 2.4% ae IPA glyphosate + 0.09 0.03 0.01 2.4% ae 2,4-D amine 870-C 2.4% ae IPA glyphosate + 0.01 0.01 0.00 2.4% ae 2,4-D amine + 2% potassium acetate

TABLE 3-6 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 563-2 1.2% ae BANVEL ® + 1.92 0.31 0.15 2.4% POWERMAX ® + 563-5 1.2% ae BANVEL ® + 0.02 0.01 0.00 2.4% POWERMAX ® + 2% potassium acetate 563-3 1.2% ae CLARITY ® + 0.49 0.13 0.06 2.4% ae PowerMAX 563-6 1.2% ae CLARITY ® + 0.01 0.01 0.00 2.4% ae POWERMAX ® + 2% potassium acetate 563-1 1.2% ae MEA dicamba + 1.04 0.24 0.12 2.4% ae POWERMAX ® + 563-4 1.2% ae MEA dicamba + 0.01 0.00 0.00 2.4% ae POWERMAX ® + 2% potassium acetate

TABLE 3-7 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 751-F 1.2% ae DGA dicamba/MEA nd na na glyphosate premix + 2% potassium acetate 210-E 1.2% ae DGA dicamba/MEA 0.07 0.01 0.00 glyphosate/ 0.54% potassium acetate premix 210-F 1.2% DGA dicamba/MEA 0.01 0.00 0.00 glyphosate premix + 2% potassium acetate/ dipotassium phosphate

TABLE 3-8 DICAMBA STD STD ID COMPOSITION (ng/L) DEV ERROR 893-A 1.2% ae CLARITY ® + 0.83 0.10 0.05 2.4% POWERMAX ® 893-B 1.2% ae CLARITY ® + 0.003 0.00 0.00 2.4% POWERMAX ® + 2% potassium acetate 893-C 1.2% ae CLARITY ® + 0.007 0.00 0.00 2.4% POWERMAX ® + 2% potassium benzoate 893-D 1.2% ae CLARITY ® + 0.003 0.00 0.00 2.4% POWERMAX ® + 2% potassium formate 893-E 1.2% ae CLARITY ® + 0.001 0.00 0.00 2.4% POWERMAX ® + 2% sodium acetate

TABLE 3-9 MOLAR MOLAR RATIO RATIO CARBOXYLIC CARBOXYLIC DICAMBA STD STD ID COMPOSITION ACID:DICAMBA ACID:KOH (ng/L) DEV ERR 836-1 1.2% ae CLARITY ®+ NA NA 1.139 0.34 0.17 2.4% POWERMAX ® 836-6 1.2% ae CLARITY ®+ NA NA 0.029 0.01 0.00 2.4% POWERMAX ®+ potassium hydroxide 836-3 1.2% ae CLARITY ®+ 2:1 1:1 0.011 0.01 0.00 2.4% POWERMAX ®+ propionic acid + potassium hydroxide 836-5 1.2% ae CLARITY ®+ 2:1 1:1 0.012 0.00 0.00 2.4% POWERMAX ®+ formic acid + potassium hydroxide 836-2 1.2% ae CLARITY ®+ 2:1 1:2 0.064 0.01 0.01 2.4% POWERMAX ®+ succinic acid + potassium hydroxide 836-4 1.2% ae CLARITY ®+ 2:1 1:1 0.014 0.01 0.00 2.4% POWERMAX ®+ acetic acid + potassium hydroxide

Example 4 Measurement of Dicamba Volatility (Plant Response)

Herbicidal compositions were sprayed onto eight 90 mm diameter glass Petri dishes. The eight Petri dishes were placed immediately on a plastic tray along with two Roundup Ready soybean plants at V1-V1.5 development stage as indicators. The plastic trays were then covered with plastic domes, sealed with clamps around edges, and placed in the growth chamber, at a set temperature and relative humidity (85° F. day (16 h light), 70° F. night (8 h dark) and 40% RH) for 24 hours. After 24 hours, the plants were removed from the domes and transferred to a greenhouse. The indicator plants were evaluated for visual symptoms typically at 5, 7 and 14 days after treatment.

Plant response results for compositions containing dicamba are listed in Table 4-1.

TABLE 4-1 (Study DCV825) ID COMPOSITION % INJURY (7 DAT) 889-A 1.2% ae DGA dicamba 15% 889-D 1.2% ae DGA dicamba + 0 2% potassium acetate

Example 5 Measurement of Herbicidal Effectiveness

The herbicidal effectiveness of the compositions of the present invention can be assessed through conventional greenhouse tests and/or field tests. Herbicidal effectiveness can be measured as a percentage “inhibition” following a standard procedure in the art which reflects a visual assessment of plant mortality and growth reduction by comparison with untreated plants, made by technicians specially trained to make and record such observations. In all cases, a single technician makes all assessments of percent inhibition within any one experiment or trial. Such measurements are relied upon and regularly reported by Monsanto Technology LLC in the course of its herbicide business.

The selection of application rates that are biologically effective for a specific auxin herbicide is within the skill of the ordinary agricultural scientist. Those of skill in the art will likewise recognize that individual plant conditions, weather and growing conditions, as well as the specific exogenous chemical and formulation thereof selected, will affect the weed efficacy and associated crop injury achieved in practicing this invention. Useful application rates for the auxin herbicides employed can depend upon all of the above conditions. With respect to the use of the method of this invention, much information is known about appropriate auxin application rates, and a weed control practitioner can select auxin application rates that are herbicidally effective on particular species at particular growth stages in particular environmental conditions.

Effectiveness in greenhouse tests, usually at exogenous chemical rates lower than those normally effective in the field, is a proven indicator of consistency of field performance at normal use rates.

The compositions of the present invention can be applied to plants by spraying, using any conventional means for spraying liquids, such as spray nozzles, atomizers, or the like. Compositions of the present invention can be used in precision farming techniques, in which apparatus is employed to vary the amount of exogenous chemical applied to different parts of a field, depending on variables such as the particular plant species present, soil composition, and the like. In one embodiment of such techniques, a global positioning system operated with the spraying apparatus can be used to apply the desired amount of the composition to different parts of a field.

The composition, at the time of application to plants, is preferably dilute enough to be readily sprayed using standard agricultural spray equipment. Preferred application rates for the present invention vary depending upon a number of factors, including the type and concentration of active ingredient and the plant species involved. Useful rates for applying an aqueous composition to a field of foliage can range from about 25 to about 1,000 liters per hectare (1/ha) by spray application. The preferred application rates for aqueous solutions are in the range from about 50 to about 3001/ha.

Many exogenous chemicals (including auxin herbicides) must be taken up by living tissues of the plant and translocated within the plant in order to produce the desired biological (e.g., herbicidal) effect. Thus, it is important that an herbicidal formulation not be applied in such a manner as to excessively injure and interrupt the normal functioning of the local tissue of the plant so quickly that translocation is reduced. However, some limited degree of local injury can be insignificant, or even beneficial, in its impact on the biological effectiveness of certain exogenous chemicals.

Example 6 Herbicidal Efficacy on ABUTH (Velvetleaf) and ELEIN (Goosegrass)

The herbicidal tank mix compositions listed in the tables below were prepared using CLARITY® (DGA dicamba from BASF) and ROUNDUP POWERMAX® (potassium glyphosate from Monsanto) by successively adding each specified herbicide to water and mixing. The tank mixtures containing potassium acetate were prepared as described in Example 1.

Weed seeds were planted in 3.5 in square plastic pots filled with Redi-earth (Sun Gro, Bellevue, Wash.) containing 100 g/cu ft Osmocote 14-14-14 slow release fertilizer. Ten to fifteen weed seeds were planted about one-half inch deep and loosely covered with Redi-Earth potting media. The pots were placed in a controlled environment equipped with sub-irrigation. Growth conditions were 27° C. day and 21° C. night with fourteen hours of supplemental light (approximately 600 microeinsteins). After germination and emergence from the potting media, the plants were thinned to achieve one plant per pot. Pots that contained plants that were similar in appearance, size, and vigor were selected for treatment. Typically, the plants were four to eight inches tall at the time of herbicide treatment. Compositions were applied to the plants with a track sprayer generally using a Teejet 9501E flat fan nozzle or similar nozzle with air pressure set at a minimum of 24 pounds per square inch. The spray nozzle was 16 inches above the top of the plants and a spray volume rate of approximately 10 gallons per acre (93 L per hectare) was applied. Each composition was applied at three application rates and herbicide injury rating was made 21 days post treatment.

TABLE 6-1 Herbicidal Efficacy of Tank Mixtures Containing POWERMAX ® and DGA dicamba/potassium acetate on ABUTH (velvetleaf) and ELEIN (goosegrass) % CONTROL AMT (21 DAT) COMPOSITION (% ae) RATE ABUTH ELEIN POWERMAX ® 39.8 140 ae g/ha 0.0 23.3 280 ae g/ha 52.5 85.0 560 ae g/ha 74.2 93.8 CLARITY ® 40 70 ae g/ha 10.0 0.0 140 ae g/ha 18.3 10.0 280 ae g/ha 36.7 10.0 503-1 31.0 70 ae g/ha 10.8 0.0 503-1 31.0 140 ae g/ha 19.2 0.0 503-1 31.0 280 ae g/ha 33.3 0.0 503-3 31.0 70 ae g/ha 10.0 8.3 503-3 31.0 140 ae g/ha 17.5 11.7 503-3 31.0 280 ae g/ha 35.0 7.5 295-3 31.0 70 ae g/ha 13.3 8.3 295-3 31.0 140 ae g/ha 20.0 11.7 295-3 31.0 280 ae g/ha 36.7 7.5 295-6 31.0 70 ae g/ha 12.5 0.0 295-6 31.0 140 ae g/ha 21.7 0.0 295-6 31.0 280 ae g/ha 43.3 3.3 POWERMAX ® 39.8 140 ae g/ha 14.2 38.3 CLARITY ® 40 70 ae g/ha POWERMAX ® 39.8 280 ae g/ha 46.7 85.0 CLARITY ® 40 140 ae g/ha POWERMAX ® 39.8% ae 560 ae g/ha 80.8 95.0 CLARITY ® 40% ae 280 ae g/ha POWERMAX ® 39.8% ae 140 ae g/ha 11.7 39.2 503-1 31.0% ae 70 ae g/ha POWERMAX ® 39.8% ae 280 ae g/ha 62.5 81.7 503-1 31.0% ae 140 ae g/ha POWERMAX ® 39.8% ae 560 ae g/ha 82.5 94.2 503-1 31.0% ae 280 ae g/ha POWERMAX ® 39.8% ae 140 ae g/ha 15.0 35.0 503-3 31.0% ae 70 ae g/ha POWERMAX ® 39.8% ae 280 ae g/ha 49.2 83.3 503-3 31.0% ae 140 ae g/ha POWERMAX ® 39.8% ae 560 ae g/ha 83.3 93.3 503-3 31.0% ae 280 ae g/ha POWERMAX ® 39.8% ae 140 ae g/ha 15.8 26.7 295-3 31.0% ae 70 ae g/ha POWERMAX ® 39.8% ae 280 ae g/ha 54.2 82.5 295-3 31.0% ae 140 ae g/ha POWERMAX ® 39.8% ae 560 ae g/ha 83.3 90.0 295-3 31.0% ae 280 ae g/ha POWERMAX ® 39.8% ae 140 ae g/ha 17.5 42.5 295-6 31.0% ae 70 ae g/ha POWERMAX ® 39.8% ae 280 ae g/ha 55.0 80.0 295-6 31.0% ae 140 ae g/ha POWERMAX ® 39.8% ae 560 ae g/ha 85.8 85.0 295-6 31.0% ae 280 ae g/ha UNTREATED 0 0 0.0 1.0 CHECK

Herbicidal premix compositions listed in the tables below were prepared as previously described in Example 2.

TABLE 6-2 Herbicidal efficacy of pre-mix composition containing glyphosate, dicamba and potassium acetate on ABUTH (velvetleaf) and ELEIN (goosegrass) % CONTROL (21 DAT) COMPOSITION ABUTH ELEIN RATE POWERMAX ® 140 ae g/ha 21.7 78.3 280 ae g/ha 71.7 95.0 560 ae g/ha 84.2 99.0 CLARITY ® 70 ae g/ha 20.0 0.0 140 ae g/ha 36.7 0.0 280 ae g/ha 60.8 0.0 POWERMAX ® 140 ae g/ha 26.7 81.7 CLARITY ® 70 ae g/ha POWERMAX ® 280 ae g/ha 59.2 90.0 CLARITY ® 140 ae g/ha POWERMAX ® 560 ae g/ha 85.8 92.5 CLARITY ® 280 ae g/ha RATE GLY/DICAMBA 287-5 140/70 ae g/ha 20.0 0.0 280/140 ae g/ha 51.7 10.0 560/280 ae g/ha 71.7 68.3 287-6 140/70 ae g/ha 18.3 0.0 280/140 ae g/ha 50.0 10.0 560/280 ae g/ha 73.3 39.2 512-1 140/70 ae g/ha 22.5 84.2 280/140 ae g/ha 64.2 93.3 560/280 ae g/ha 92.7 97.2 248-1 140/70 ae g/ha 32.5 78.3 280/140 ae g/ha 63.3 92.2 560/280 ae g/ha 85.5 95.0 248-2 140/70 ae g/ha 38.3 78.3 280/140 ae g/ha 57.5 93.3 560/280 ae g/ha 85.8 95.0 248-3 140/70 ae g/ha 30.0 80.8 280/140 ae g/ha 51.7 90.8 560/280 ae g/ha 84.7 96.5 249-1 140/70 ae g/ha 33.3 81.7 280/140 ae g/ha 59.2 90.0 560/280 ae g/ha 92.2 98.0 249-2 140/70 ae g/ha 30.0 80.8 280/140 ae g/ha 58.3 90.8 560/280 ae g/ha 89.7 97.3 249-3 140/70 ae g/ha 30.8 86.7 280/140 ae g/ha 63.3 91.7 560/280 ae g/ha 86.7 98.2 UNTREATED CHECK 0 0.0 0.0

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. 

What is claimed is:
 1. A herbicidal composition concentrate comprising: (a) at least one auxin herbicide; and (b) at least one monocarboxylic acid, or a monocarboxylate thereof; wherein the concentrate satisfies one or more of the following conditions: the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1; the concentrate comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.25% to about 25% by weight of the concentrate; the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and the concentrate comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the concentrate by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical concentrate lacking the monocarboxylic acid, or monocarboxylate thereof.
 2. The herbicidal composition concentrate of claim 1, wherein the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1.
 3. The herbicidal composition concentrate of claim 1, wherein the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.
 4. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.25% to about 25% by weight of the concentrate.
 5. The herbicidal composition concentrate of claim 1, wherein: the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1; and the concentrate comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.25% to about 25% by weight of the concentrate.
 6. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises dicamba, or an agriculturally acceptable salt or ester thereof.
 7. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises 2,4-D, or an agriculturally acceptable salt or ester thereof.
 8. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises acetic acid, or an agriculturally acceptable salt thereof.
 9. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises dicamba, or an agriculturally acceptable salt or ester thereof, and acetic acid, or an agriculturally acceptable salt thereof.
 10. The herbicidal composition concentrate of claim 1, wherein the concentrate comprises 2,4-D, or an agriculturally acceptable salt or ester thereof, and acetic acid, or an agriculturally acceptable salt thereof.
 11. The herbicidal composition concentrate of claim 1, wherein the concentrate further comprises a non-auxin herbicide.
 12. The herbicidal composition concentrate of claim 11, wherein the non-auxin herbicide is glyphosate, or an agriculturally acceptable salt thereof.
 13. The herbicidal composition concentrate of claim 11, wherein the non-auxin herbicide is glufosinate, or an agriculturally acceptable salt thereof.
 14. The herbicidal composition concentrate of claim 11, wherein the concentrate satisfies one or more of the following conditions: the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 120 grams (acid equivalent weight)/L to about 600 grams (acid equivalent weight)/L; the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.
 15. The herbicidal composition concentrate of claim 1, wherein the concentrate is a dry herbicidal composition.
 16. The herbicidal composition concentrate of claim 1, wherein the concentrate is a liquid herbicidal composition.
 17. A herbicidal composition comprising: (a) at least one auxin herbicide; (b) at least one monocarboxylic acid, or a monocarboxylate thereof; and (c) water; wherein the composition optionally comprises a non-auxin herbicide; and wherein the composition satisfies one or more of the following conditions: the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1; the composition comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.1% to about 25% by weight of the composition; the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and the composition comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the composition by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical composition lacking the monocarboxylic acid, or monocarboxylate thereof.
 18. The herbicidal composition of claim 17, wherein the composition comprises dicamba, or an agriculturally acceptable salt or ester thereof; and acetic acid, or an agriculturally acceptable salt thereof.
 19. The herbicidal composition concentrate of claim 17, wherein the composition comprises a non-auxin herbicide and satisfies one or more of the following conditions: the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 1 gram (acid equivalent weight)/L to about 50 grams (acid equivalent weight)/L; the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.
 20. The herbicidal composition of claim 19, wherein the composition comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glyphosate, or an agriculturally acceptable salt thereof.
 21. The herbicidal composition concentrate of claim 19, wherein the composition comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glufosinate, or an agriculturally acceptable salt thereof.
 22. An adjuvant composition for use in the preparation of an aqueous herbicidal application mixture, the composition comprising: (a) acetic acid, or an agriculturally acceptable salt thereof; and (b) alkali metal phosphate; wherein the composition satisfies one or both of the following conditions: the molar ratio of acetic acid, or agriculturally acceptable salt thereof, to alkali metal phosphate is from about 1:5 to about 5:1; and the composition comprises an amount (acid equivalent weight) of the acetic acid, or agriculturally acceptable salt thereof, from about 2% to about 40% by weight of the composition.
 23. A method of controlling the growth of auxin-susceptible plants, the method comprising the steps of: preparing an aqueous herbicidal application mixture comprising an auxin herbicide; a monocarboxylic acid, or a monocarboxylate thereof; and water; and applying a herbicidally effective amount of the application mixture to the auxin-susceptible plants; wherein the application mixture satisfies one or more of the following conditions: the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1; the composition comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.1% to about 25% by weight of the application mixture; the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and the application mixture comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the application mixture by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.
 24. The method of claim 22, wherein the aqueous herbicidal application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; and acetic acid, or an agriculturally acceptable salt thereof.
 25. The method of claim 22, wherein the aqueous herbicidal application mixture further comprises a source of non-auxin herbicide.
 26. The method of claim 25, wherein the application mixture satisfies one or more of the following conditions: the sum of the concentration of auxin herbicide and the concentration of non-auxin herbicide is from about 1 gram (acid equivalent weight)/L to about 50 grams (acid equivalent weight)/L; the acid equivalent weight ratio of auxin herbicide to non-auxin herbicide is from about 1:5 to about 2:1; and the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1.
 27. The method of claim 25, wherein the application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glyphosate, or an agriculturally acceptable salt thereof.
 28. The method of claim 25, wherein the application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glufosinate, or an agriculturally acceptable salt thereof.
 29. A method of controlling off-site movement of an auxin herbicide, the method comprising the steps of: preparing an aqueous herbicidal application mixture comprising an auxin herbicide; a monocarboxylic acid, or a monocarboxylate thereof; and water; and applying a herbicidally effective amount of the application mixture to auxin-susceptible plants; wherein the application mixture satisfies one or more of the following conditions: the molar ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of monocarboxylic acid, or monocarboxylate thereof, to auxin herbicide is from about 1:10 to about 5:1; the composition comprises an amount (acid equivalent weight) of the monocarboxylic acid, or monocarboxylate thereof, from about 0.1% to about 25% by weight of the application mixture; the concentration of the monocarboxylic acid, or monocarboxylate thereof, is from about 1 gram (acid equivalent weight)/L to about 250 grams (acid equivalent weight)/L; and the application mixture comprises an amount of the monocarboxylic acid, or monocarboxylate thereof, sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase surrounding the application mixture by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase surrounding an otherwise identical application mixture lacking the monocarboxylic acid, or monocarboxylate thereof.
 30. The method of claim 29, wherein the application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; and acetic acid, or an agriculturally acceptable salt thereof.
 31. The method of claim 29, wherein the application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glyphosate, or an agriculturally acceptable salt thereof.
 32. The method of claim 29, wherein the application mixture comprises dicamba, or an agriculturally acceptable salt or ester thereof; acetic acid, or an agriculturally acceptable salt thereof; and glufosinate, or an agriculturally acceptable salt thereof.
 33. A method of reducing the volatility of an auxin herbicide, the method comprising the step of contacting the auxin herbicide with a volatility-lowering effective amount of a monocarboxylic acid, or a monocarboxylate thereof.
 34. The method of claim 33, wherein at least one of the following conditions is satisfied: the molar ratio of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is from about 1:10 to about 10:1; the acid equivalent weight ratio of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is from about 1:10 to about 5:1; and the amount of the monocarboxylic acid, or monocarboxylate thereof, contacted with the auxin herbicide is sufficient to reduce the concentration of volatilized auxin herbicide in the vapor phase by at least 10% relative to the concentration of volatilized auxin herbicide in the vapor phase for an auxin herbicide in the absence of the monocarboxylic acid, or monocarboxylate thereof.
 35. The method of claim 34, wherein the auxin herbicide comprises dicamba, or an agriculturally acceptable salt or ester thereof; and the monocarboxylic acid, or monocarboxylate thereof, is acetic acid, or an agriculturally acceptable salt thereof.
 36. A method of counseling an individual on the application of an auxin herbicide to auxin-susceptible plants, the method comprising: (a) identifying a source of an auxin herbicide; (b) instructing the individual to prepare an aqueous herbicidal application mixture from the source of auxin herbicide; and (c) additionally instructing the individual to supplement the application mixture with a monocarboxylic acid, or monocarboxylate thereof, prior to the application of the application mixture to the auxin-susceptible plants.
 37. The method of claim 36, wherein the auxin herbicide comprises dicamba, or an agriculturally acceptable salt or ester thereof; and the monocarboxylic acid, or monocarboxylate thereof, is acetic acid, or an agriculturally acceptable salt thereof.
 38. A method of counseling an individual on the application of an auxin herbicide to auxin-susceptible plants, the method comprising: (a) identifying a source of an auxin herbicide; (b) identifying a source of a monocarboxylic acid, or a monocarboxylate thereof; and (c) instructing the individual to prepare an aqueous herbicidal application mixture from the source of auxin herbicide and the source of monocarboxylic acid, or monocarboxylate thereof, for application to the auxin-susceptible plants.
 39. The method of claim 38, wherein the auxin herbicide comprises dicamba, or an agriculturally acceptable salt or ester thereof; and the monocarboxylic acid, or monocarboxylate thereof, is acetic acid, or an agriculturally acceptable salt thereof. 